Why does ice float on water ?

"Ice is less dense than water because of its intermolecular forces."

Water contains hydrogen bonds (a type of intermolecular force of attraction) between the H (hydrogen) of one atom and the O (oxygen) of another atom.  As the water gets colder and the kinetic energy of the molecules decreases, the hydrogen bonds keep the water molecules apart, forming hexagonal structures with water molecules at each vertex.  In between the water molecules is nothing.  In liquid water, the molecules of water can be much closer together; the hydrogen bonds are more flexible.  Therefore, the solid ice, with its molecules kept at a fairly fixed distance and the crystals holding lots of "nothing" among the water molecules, is less dense than the liquid water.

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Can anything travel faster than light ??

What Travels Faster Than the Speed of Light ??

 

Many people wants to know that ,can anything travel faster than speed of light..?? or simply What Travels Faster Than the Speed of Light ??If you have the same question than here is the answer :

Most textbooks say that nothing can go faster than light, but that statement actually should be qualified: The answer is yes, you can break the light barrier, but not in the way we see in the movies. There are, in fact, several ways to travel faster than light:

1. The Big Bang itself expanded much faster than the speed of light. But this only means that "nothing can go faster than light." Since nothing is just empty space or vacuum, it can expand faster than light speed since no material object is breaking the light barrier. Therefore, empty space can certainly expand faster than light.

2. If you wave a flashlight across the night sky, then, in principle, its image can travel faster than light speed (since the beam of light is going from one part of the Universe to another part on the opposite side, which is, in principle, many light years away). The problem here is that no material object is actually moving faster than light. (Imagine that you are surrounded by a giant sphere one light year across. The image from the light beam will eventually hit the sphere one year later. This image that hits the sphere then races across the entire sphere within a matter of seconds, although the sphere is one light year across.) Just the image of the beam as it races across the night sky is moving faster than light, but there is no message, no net information, no material object  that actually moves along this image.

3. Quantum entanglement moves faster than light. If I have two electrons close together, they can vibrate in unison, according to the quantum theory. If I then separate them, an invisible umbilical cord emerges which connects the two electrons, even though they may be separated by many light years. If I jiggle one electron, the other electron "senses" this vibration instantly, faster than the speed of light. Einstein thought that this therefore disproved the quantum theory, since nothing can go faster than light.

But actually this experiment (the EPR experiment) has been done many times, and each time Einstein was wrong. Information does go faster than light, but Einstein has the last laugh. This is because the information that breaks the light barrier is random, and hence useless. (For example, let's say a friend always wears one red sock and one green sock. You don't know which leg wears which sock. If you suddenly see that one foot has a red sock, then you know instantly, faster than the speed of light, that the other sock is green. But this information is useless. You cannot send Morse code or usable information via red and green socks.)

4. The most credible way of sending signals faster than light is via negative matter. You can do this either by:

a) compressing the space in front of your and expanding the space behind you, so that you surf on a tidal wave of warped space. You can calculate that this tidal wave travels faster than light if driven by negative matter (an exotic form of matter which has never been seen.) b) using a wormhole, which is a portal or shortcut through space-time, like the Looking Glass of Alice.

In summary, the only viable way of breaking the light barrier may be through General Relativity and the warping of space time. However, it is not known if negative matter exists, and whether the wormhole will be stable. To solve the question of stability, you need a fully quantum theory of gravity, and the only such theory which can unite gravity with the quantum theory is string theory (which is what I do for a living). Sadly, the theory is so complex that no has been able to fully solve it and give a definitive anwer to all these questions. Maybe someone reading this blog will be inspired to sovle string theory and answer the question whether we can truly break the light barrier.

 

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What is electricity and How Electricity is Produced ?

What is electricity ?

Electricity is a form of energy that starts with atoms. You can't see atoms because they're too small, but they make up everything around us. There are three parts to an atom: protons, neutrons and electrons. Electricity is created when electrons move from atom to atom. There are a number of ways to make electrons move, but most electricity is produced at power plants.

How do power plants work ?

Power plants that use water to make electricity are built near rivers.Dams are built across rivers to hold back the water. The water is then directed through big pipes and it falls against the blades of giant turbines. The turbines have blades on them that turn when the water hits them, just like the blades of a pinwheel turn when you blow on them. Once the water hits the blades, it returns to the river.

The turbine blades are attached to a big metal rod, and at the end of that rod are large magnets. When the blades turn, they make the rod and the magnets spin very fast. The magnet end is surrounded by heavy coils of copper wire, and the spinning magnets cause electrons in the wire to begin to move, creating electricity.

What happens to the electricity after that ?

It moves through wires into what's called a power transformer. The electrical voltage (the strength at which electricity flows) is fairly high and the transformer makes it even higher to help it flow through wires called transmission lines. Those wires are attached to wooden or metal poles that you see along roads and throughout communities.

All the wires are made of metal – usually aluminum or copper. That's because metal is a good conductor – electricity travels through it easily. By the way, water is also a good conductor, and because our bodies are mostly made of water, electricity can travel through us easily. That's not something we want to happen though, because if we have electricity going through us we'll likely be seriously hurt or even killed. That's why grown-ups warn you to stay away from high voltage sites and not to stick your fingers in a wall plug.

Electricity travels fast – about 310,000 kilometers per second! If you moved that fast, you could probably make several trips around the world in the time it takes to turn on a light!

Sometimes, when electricity has to travel a long way it gets a little weaker as it moves along the lines. It needs a boost (like you need food to replace the energy you've burned after playing outside all day). That's where substations help. Substations are large box-like power transformers that sit in fenced-in areas. You'll see signs on the fences that say high voltage – stay away and it's really important that you obey those signs (remember what you read about electricity being able to travel easily through your body).

How does electricity get into my house ?

When wires reach your house, another transformer on the power pole makes the electricity just the right voltage so you can use it safely.

The wire is connected to a meter box that keeps track of how much electricity is being used. There are wires in your house connected to plugs, also called outlets. These outlets let you plug in your boom box, television set, or any thing else electrical. What an amazing journey electricity takes to get to your home !!

 

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We know the Earth is rotating, but why?

Why is everything in the Solar System spinning? And why is it mostly all spinning in the same direction?

 

Why is everything in the Solar System spinning? And why is it mostly all spinning in the same direction?

It can’t be a coincidence. Look down on the Earth from above, and you’d see that it’s turning in a counter-clockwise direction. Same with the Sun, Mars and most of the planets.  

4.54 billion years ago, our Solar System formed within a cloud of hydrogen not unlike the Orion Nebula, or the Eagle Nebula, with its awesome pillars of creation. Then, it took some kick, like from the shock wave from a nearby supernova, and this set a region of the cold gas falling inward through its mutual gravity. As it collapsed, the cloud began to spin.

But why?

It’s the conservation of angular momentum.

Think about the individual atoms in the cloud of hydrogen. Each particle has its own momentum as it drifts through the void. As these atoms glom onto one another with gravity, they need to average out their momentum. It might be possible to average out perfectly to zero, but it’s really really unlikely.

Which means, there will be some left over. Like a figure skater pulling in her arms to spin more rapidly, the collapsing proto-Solar System with its averaged out particle momentum began to spin faster and faster.

This is the conservation of angular momentum at work.

As the Solar System spun more rapidly, it flattened out into a disk with a bulge in the middle. We see this same structure throughout the Universe: the shape of galaxies, around rapidly spinning black holes, and we even see it in pizza restaurants.

The Sun formed from the bulge at the center of this disk, and the planets formed further out. They inherited their rotation from the overall movement of the Solar System itself. Over the course of a few hundred million years, all of the material in the Solar System gathered together into planets, asteroids, moons and comets. Then the powerful radiation and solar winds from the young Sun cleared out everything that was left over.

Without any unbalanced forces acting on them, the inertia of the Sun and the planets have kept them spinning for billions of years.

And they’ll continue to do so until they collide with some object, billions or even trillions of years in the future.

So are you still wondering, why does the Earth spin?

The Earth spins because it formed in the accretion disk of a cloud of hydrogen that collapsed down from mutual gravity and needed to conserve its angular momentum. It continues to spin because of inertia.

The reason it’s all the same direction is because they all formed together in the same Solar Nebula, billions of years ago.

 

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What Causes Optical Illusions?

What Causes Optical Illusions?

These yellow and blue blocks appear to move one after the other but actually not..!!

In simple terms, an optical illusion is caused by the structure of both the eye and brain and how they work together. Because of the anatomical make up of the eye and the complexity of the way images of transmitted from the eye to the brain, optical illusions are not as rare as one might consider.

The Anatomy of the Eye

The eye has two types of receptors on it (cones and rods) that pick up different bits of information on image. Around the retina, these cones and rods rest, waiting to pick up a stimuli and transfer it to the optic nerve. The optic nerve, in turn, transmits the information to the brain for processing.

Cone cells detect color and rod cells detect low-light contrasts. They work together to provide the necessary information to form an imag. However, at the edges of the retina, there are more rods and at the center of the retina, there are more cones. Because of this, based on how someone is looking at an image, they might see things differently. This is an optical illusion. For a better image, simply turning one's head and looking straight at something will provide the cones access and give a more detailed image.

Medical Syndromes Causing Optical Illusions

There is research to suggest that some optical illusions are caused by medical syndromes such as schizophrenia. Because of the nature of the disease, an individual sees something different than what is actually being seen. This is caused by the brain interpreting the information differently than it normally would be.

Effort on the Eye

Because it is more difficult to raise the eye than move the eye horizontally, the eye perceives that vertical distances are greater than horizontal distances. This creates depth in flat surfaces which can – especially when the eyes are fatigued – lead them to perceive something incorrectly and then pass that information onto the brain. The brain takes what information it has and processes it whether it is correct or not. Fatigue in the eyes is an exceptional cause of optical illusions because it takes a little longer for the eyes to focus more effectively.

 

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What is the use of integration and differentiation?

What is the use of integration and differentiation?

Let us get into this with all interest. Yes integration is a reverse process of differentiation.
First let us put the question why do we need such a mathematical process called integration. Actually integration is nothing but the summing up of a lot, some million and million items.
Let me explain how.
Suppose you want to find the volume of a cone of radius r and height h.
Let the cone be seated such that its vertex get coincided with the origin and its height be along the x -axis.
In case of a cylinder the radius will be the same at all heights and so if you consider a small part both the sides of that part will have the same radius and so no problem in finding the volume.
But in the case of the cone, as we move away from the origin along x-axis the radius of the cone will be gradually increasing.
So as you consider a slice any where in the cone both the sides of the slice will not definitely have same radius. Is that ok?
Now calculus comes into play.
You choose a small slice in such a way that both the sides of the slice would have almost the same radius. It is possible only when you have a slice of negligible thickness. Such negligible thickness is denoted mathematically denoted as dx which means delta x tending to zero.
Once again note down the statement: delta x tending to zero. This means delta x is very so near to zero but not zero.
With such....... thickness, both sides of the slice would have the same radius.Let the slice of thickness dx be chosen at a distance x from the origin and let the radius of the slice be y at that position. Then the volume of our slice will be pi y^2 dx. Now imagine! Such slices, innumerable in number, can be got in the cone right moving from the origin and extending upto the total length (height) h of the cone. So we must collect all such slices and add their volumes to get the actual or total volume of the cone.
So we integrate the term pi y^2 dx within the limits of x ie 0 to h.
Now it becomes more essential to replace y interms of x. How can we do this? By using similar triangle concept, the ratio of the corresponding sides will be the same. So y/x = r/h
From this we can easily have y as (r/h) x.
Now replacing y we get the expression to be integrated (usually named as integrand) as pi (r/h)^2 x^2 dx. The formula for integral of x^n dx is given as x^(n+1) /(n+1).
So following this we get the integral value as pi(r/h)^2 (x^3 /3).
Next important step is supplying limit of x.
First upper limit h. This would give a value of pi(r/h)^2 (h^3 /3)
With lower limit 0, the value would become 0
Now the difference between these two values will be the required volume of the cone.
That comes to be 1/3 pi r^2 h. (cancelling h^2)
So interesting! See how much helpful the technique of integration in finding the volume of the cone!
By differentiation, we chop things into finer and by integration we collect all such finer.
Hope you have got a gist of the tremendous usage of the branch of mathematics, named as calculus.

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Explain why the moon has no atmosphere..?

Moon has no atmosphere because the value of acceleration due to gravity ‘g’ on the surface of moon is small. Therefore, the value of escape velocity on the surface of moon is small. The value of r.m.s. velocity of the molecules of different gases is much above the value of escape velocity on moon. That is why all the molecules of gases escaped and there is no atmosphere on moon.

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What Is the Difference Between Mass and Weight?

Comparison of Mass and Weight

Mass is a property of matter. The mass of an object is the same everywhere,	Weight depends on the effect of gravity. Weight varies according to location.
Mass can never be zero.	Weight can be zero if no gravity acts upon an object, as in space.
Mass does not change according to location.	Weight increases or decreases with higher or lower gravity.
Mass is a scalar quantity. It has magnitude.	Weight is a vector quantity. It has magnitude and is directed toward the center of the Earth or other gravity well.
Mass may be measured using an ordinary balance.	Weight is measured using a spring balance.
Mass usually is measured in grams and kilograms.	Weight often is measured in newtons, a unit of force.

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Does a fully charged battery weight more than when it's empty?

Does a fully charged battery weight more than when it's empty?

Yes because of E= mc*2
When you test the electrolite in a lead acid battery,as the battery charges the sulphuric acid becomes denser which gives it more mass so it "weighs" more.

Try it at home weigh a flat car battery on some reasonably accurate scales then charge it up and weigh it again.All you have added is potential energy.

The speed of light is constant,the energy has increased(it will start your car) so the only thing that can change is the mass.

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Is the number 0 even or odd..?

Is the number 0 even or odd..? 

 

A number is even if it is divisible by 2 without a remainder. For Example 8 is even since 8 divided by 2 is 4, and 12 is even since 12 divided by 2 is 6, but 7 is not even since 7 divided by 2 is 3 with a remainder of 1. 

What about zero? Zero divided by 2 is zero with no remainder so zero is even. 

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What would happen if Earth stopped spinning ?

What would happen if Earth stopped spinning ..?? 

 

 As you probably know, the Earth is rotating on its axis. This gives us day and night. Of course it’s impossible, but what would happen if the Earth stopped spinning? Remember, this isn’t possible, it can’t happen, so don’t worry.

Everything would be launched in a ballistic trajectory sideways
The first thing to think about is the momentum of everything on the surface of the Earth. You’re held down by gravity and you’re whizzing through space at a rotational velocity of 1,674.4 km/h (at the equator). You can’t feel it because of momentum. Just like how you can’t feel that you’re moving in a car going down the highway. But you feel the effects when you stop, or get into an accident. And so, if the Earth suddenly stopped spinning, everything on the surface of the Earth at the equator would suddenly be moving at more than 1,600 km/hour sideways. The escape velocity of Earth is about 40,000 km/hour, so that isn’t enough to fly off into space; but it would cause some horrible damage as everything flew in a ballistic trajectory sideways. Imagine the oceans sloshing sideways at 1,600 km/hour.

The rotational velocity of the Earth decreases as you head away from the equator, towards the poles. So as you got further away from the equator, your speed would decrease. If you were standing right on the north or south pole, you’d barely even feel it.

A day would last 365 days
The next problem is that day and night wouldn’t work the same any more. Right now the Earth is rotating on its axis, returning the Sun to the same position every 24 hours. But if the Earth stopped spinning, it would then take 365 days for the Sun to move through the sky and return to the same position. Half of the Earth would be baked for half a year, while the other hemisphere was in darkness. It would get very hot on the sunny side, and very cold in the shadowed side. You can imagine how that would be devastating to plants and animals. We get a hint of this at the poles, where you can experience weeks of permanent night and then weeks of permanent day. But imagine 6 months of night, followed by 6 months of day.

What Would Happen if the Earth Stopped Spinning

The Earth would become a perfect sphere
This might seem minor compared to the other catastrophes, but the Earth would become an almost perfect sphere. The Earth is currently rotating on its axis, completing one turn approximately every 24 hours. This rotational velocity causes the Earth to bulge out around its equator, turning our planet into an oblate spheroid (a flattened ball). Without this spin, gravity would be able to pull the Earth into a nice perfect sphere. This sounds interesting and probably harmless, but it’s actually a *big* problem. Because of the Earth’s bulge in the middle, the oceans are held out at the equator by 8 km. On perfect sphere Earth, the world’s oceans would redistribute, flooding many regions of the planet with an immense volume of water. We’d end up with a single continent around the middle of the planet, with oceans surrounding the north and south poles.

The Earth would no longer be tilted
The Earth’s tilt is defined by how the planet is rotating compared to the Sun. This axis of rotation defines the Earth’s seasons. But without any rotation, the concept doesn’t make sense any more. There’s still a north pole of the planet, where the radiation from the Sun is at its lowest angle, and an equator, where the light hits most directly. But there would no longer be seasons.

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Interesting Facts About Earth

Interesting Facts About Earth

 

Earth is the place that each person calls home. It is home to over six billion people and around 8.7 million different species. While everyone lives on Earth, there are many interesting facts that people do not know about the planet. Earth is unique in our solar system as being the only known planet to support the multitudes of different life. Earth facts can reveal the true nature of the place life calls home.

The Earth is not a Perfect Circle

It was long thought that Earth was spherical in shape. After careful studies and measurements by scientists, it is now known that earth is more of an oval. If you look at the diameter from pole to pole, Earth is 7882.4 miles long. If you measure the diameter from the equator line, earth measures 7908.9 miles long. The reason for the difference is how the Earth spins. It spins on its axes, which goes through the poles, making some of its mass move away from the poles and to its outside center.

There are Few Craters on Earth

When Earth is compared to the Moon, it has less impact craters caused by space debris. The Moon is documented to have billions of craters, as can be seen by looking at it. The reason behind so few craters on the Earth is that Earth possesses an atmosphere, which creates fiction for anything coming into it. The friction caused by an object moving at hundreds of thousands of miles per second entering the Earth?s atmosphere causes the object to burn up before hitting the ground. The Moon has no atmosphere and cannot stop even the smallest meteor hitting its surface, which is why there are so many craters on the Moon.

The Earth's Atmosphere

The atmosphere around the Earth keeps the animals and creatures living upon its surface a great deal as far as the requirements of life goes. It weighs around five trillions tons altogether, which is calculated based on the atmospheric pressure it exudes on the surface. The pressure is around one kilogram per square centimeter. The atmosphere protects its inhabitants from harmful space objects like meteors by burning them up before impact as well as harmful light rays such as X-rays, ultraviolet light, infrared and gamma rays.

Gravity is not the Same Everywhere

v There is an area in Canada called Hudson Bay that has a lower gravitational force than other regions of the earth. Scientists believe that 25 to 45 percent of the gravitational flux is due to a giant glacier sheet that was in the area long ago causing the Earth's crust to subside somewhat. The rest of the reason behind the gravitational flux can be explained by down drag due to the magma in the Earth's mantle.

The place that all known living creatures live is a fascinating place. The Earth facts discussed in this article can give an idea of the type of place life call home. The most important thing that people of planet Earth can do is to look after Earth so that all future generations can experience the wonders that Earth holds.

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In the earth where the gravity of the earth becomes zero..?

In the earth where the gravity of the earth becomes zero..?

In a perfectly-shaped sphere, with a smooth surface, and composed of exactly the same substance with the same density throughout it, the force of gravity is zero at the exact center of the sphere. That does NOT mean that 'gravity becomes zero' at the center. It means that at the center, for every speck of mass pulling on you in any direction with any force, there's another speck of mass pulling you in exactly the opposite direction with exactly the same amount of force, so the whole thing adds up to zero. In the real Earth, we can't tell exactly where that point is, because the Earth is not a perfect sphere shape, It doesn't have a smooth surface, and we don't know every last little detail about the distribution of mass inside it.

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Can you have zero gravity conditions on Earth..?

 Can you have zero gravity conditions on Earth..?

Gravity will always be there, but you can set up an arrangement where you will appear to be weightless. Such an arrangement is in a plane that flies up and swoops down so that its path is a circle standing on edge. You will hang in the plane and appear to be weightless. What is actually happening is that for a few seconds the plane is falling at the same speed as you are so if you measured your weight on scales in the plane, you would appear to weigh zero.

Zero gravity is impossible on earth. Actually, zero gravity is impossible anywhere. Gravity acts through millions of light-years, holding galaxy groups together, so there's no way that you can eliminate gravity this close to a major mass like the earth.

However - you CAN have a situation that is mathematically and physically equivalent to zero gravity, and that is free fall. Jump on a trampoline, you'll spend a few fractions of a second in free fall, which is just like zero-G. NASA does it with the Vomit Comet, which is a modified KC-135 aircraft that flies in parabolic paths to give astronauts-in-training a free fall experience. 

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Which Came First, The Chicken Or The Egg?

Chickens, as a species, became chickens through a long, slow process of evolution. At some point, a chicken-like bird produced an offspring that, due to some mutation in its DNA, crossed the threshold from mere chicken likeness into chicken actuality. That is to say, a proto-chicken gave birth to a real-life official chicken. And since that real-life official chicken came out of its own egg, we can say that the egg came first.

Another way to look at the question would be to ask which came first in evolutionary history. Once again, the egg takes precedence. Many characteristics of the modern avian egg—namely an oblong, asymmetrical shape and a hardened shell—were in place before birds diverged from dinosaurs about 150 million years ago. "A lot of the traits that we see in bird eggs evolved prior to birds in theropod dinosaurs," says Darla Zelenitsky, of the University of Calgary.

Another key moment in the history of avian eggs occurred at least 150 million years before that, when a subset of four-limbed vertebrates evolved to produce amniotic eggs. The embryos within the eggs were surrounded by three fluid-filled membranes that provide nourishment, protection, and a way to breathe. The earliest amniotic eggs contained large amounts of yolk, says James R. Stewart, a reproductive physiologist at East Tennessee State University. "You still see that in birds, crocodilians, and snakes," he explains. Like other placental mammals, we humans lost our yolk somewhere along the line, but our eggs still come with a vestigial yolk sac.

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Why 0! is equal to 1 ..??

Why 0! is equal to 1 ..??

We Know ,

n! = n x (n-1)!

Dividing both sides by n , We get

n!/n = n x (n-1)!/n 

Or, n!/n = (n-1)!

Or, (n-1)! = n!/n

Now , Putting n=1 , We get

(1-1)! = 1!/1

i.e. 0! = 1 

  

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What would happen if you drilled a tunnel through the center of the Earth and jumped into it?

What would happen if you drilled a tunnel through the center of the Earth and jumped into it..?

Want to really get away from it all? The farthest you can travel from home (and still remain on Earth) is about 7,900 miles (12,700 kilometers) straight down, but you'll have to journey the long way round to get there: 12,450 miles (20,036 kilometers) over land and sea.

Why not take a shortcut, straight down? You can get there in about 42 minutes -- that's short enough for a long lunch, assuming you can avoid Mole Men, prehistoric reptiles and underworld denizens en route. Granted, most Americans would end up in the Indian Ocean, but Chileans could dine out on authentic Chinese, and Kiwis could tuck into Spanish tapas for tea [sources: NOVA; Shegelski].

Of course, you'd be in for a rough ride. First, you'd have to pass through 22-44 miles (35-70 kilometers) of continental crust (3-6 miles/5-10 kilometers on the ocean floor) followed by 1,800 miles (2,900 kilometers) of mantle. After that, you'd have to traverse a Mars-sized outer core of liquid iron churning as hot as the sun's surface (10,000 degrees F, or 5,500 degrees C), then a solid, moon-sized inner core, and, some studies suggest, a liquid innermost core [sources: Angier; Locke; NOVA].

For sake of argument (and survival) let's pretend the Earth is a cold, uniform, inert ball of rock. While we're at it, let's ignore air resistance.

At the Earth's surface, gravity pulls on us at 32 feet (9.8 meters) per second squared. That means that, for each second you fall, you speed up by 32 feet per second -- but only near Earth's surface. Gravity is a function of mass, and mass is a property of matter. On the surface, all of Earth's matter lies below your feet but, as you fall, more and more of it surrounds you, exerting its own gravity. These horizontal tugs counterbalance each other and cancel out, but the increasing proportion of mass above your head exerts a growing counterforce to the proportionately decreasing mass below, so your acceleration slows as you near the core. At the planet's center, your acceleration due to gravity is zero -- Earth's mass surrounds you, gravity cancels out and you are weightless [sources: Locke; Singh].

You're still moving at a heck of a clip, though, so don't expect to stop there. Halfway to the center, your speed hits 15,000 mph (24,000 kph); 21 minutes after jumping in, you blow past the center at 18,000 mph (29,000 kph). Another 21 minutes later, with gravity slowing you as you go, you reach the far side and stop briefly in midair. Unless someone catches you, you'll then head back the way you came and start all over again. In our idealized case, this will continue indefinitely, like a pendulum or a spring, in a process called harmonic motion

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Funniest Math/Science Questions and answers

Q. How can you drop a raw egg onto a concrete floor without cracking it?

A. Concrete floors are very hard to crack!



Q. If it took eight men ten hours to build a wall, how long would it take
four men to build it?

A. No time at all it is already built.



Q. If you had three apples and four oranges in one hand and four apples
and three oranges in the other hand, what would you have?

A. Very large hands. (Good one)



Q. How can you lift an elephant with one hand?

A. It is not a problem, since you will never find an elephant with
one hand.




Q. How can a man go eight days without sleep?

A. No Probs , He sleeps at night.



Q. If you throw a red stone into the blue sea what it will become?

A. It will Wet or Sink as simple as that.



Q. What looks like half apple ?

A: The other half.



Q. What can you never eat for breakfast ?

A: Dinner.



Q. What happened when wheel was invented ?

A: It caused a revolution.



Q. Bay of Bengal is in which state?

A: Liquid

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Math Puzzle Questions

1. What is come in place of question mark (?) in the following series?





(a) HS

(b) IT

(c) IS

(d) HT



Solution:

2. If A is substituted by 4, B by 3, C by 2, D by 4, E by 3, F by 2 and so on, then what will be total of the numerical values of the letters of the word SICK?

(a) 11

(b) 12

(c) 10

(d) 9



Solution:

Total value = 4 + 2 + 2 + 3 = 11.

Answer: (a)



3. Four of the following five are alike in a certain way and hence form a group. Which one does not belong to the group?

(a) 52

(b) 70

(c) 48

(d) 68



Solution:All the numbers are multiple of 4, except 70.

Answer: (b)



4. If U is denoted by 7, M by 2, I by 5, O by 1, K by 8 and J by 4, then what will be the numeric form of the word MOUJIK when written in the reverse order?

(a) 217458

(b) 845712

(c) 854712

(d) 857412



Solution:

217458 is the number.

Now reverse the number 854712

Answer: (c)



5. How many letters of the word FAINTS, will their order in the word and that when the letters are arranged in the alphabetical order, remain the same?

(a) Two

(b) One

(c) Three

(d) Nil



Solution:

When the letters are arranged in the alphabetical order, two remains the same.

Answer: (a)



6. In a certain code GARNISH is written as RGAINHS. How will GENIOUS be written in that code?

(a) NEGOISU

(b) NGEOISU

(c) NGESUOI

(d) NEGSUOI



Solution:

So now, GENIOUS be written as;

Answer: (b)



7. How many such pairs of letters are there in the word MISPLACE each of which has as many letters between its two letters in the word as there are between them in the English alphabet?

(a) One

(b) Nil

(c) Two

(d) Three



Solution:

Answer: (c)



8. In a certain code INKER is written as GLLGT and GLIDE is written as EJJFG. How will JINKS be written in that code?

(a) GFOMU

(b) HGMMU

(c) HGOGH

(d) HGOMU



Solution:

As,

And,

Similarly, JINKS be written as;

Answer: (d)



9. If ‘AND’ is written as ‘EQF’ and ‘THE’ as ‘XKG’ then how will ‘COM’ be written?

(a) HRO

(b) GQO

(c) GRO

(d) GRN



Solution:

As,

And,

Similarly, ‘COM’ be written as;

Answer: (c)



10. Four of the following five are alike in a certain way based on the positions of their elements in the English alphabet and hence form a group. Which one does not belong to the group?

(a) UQ

(b) KG

(c) SO

(d) QL



Solution:

QL

Answer: (d)

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The Earth revolves around the Sun at a speed of about 18.5 miles/sec (30 km/sec) during this rotation, why the atmospheric wind is not felt by the earth?

The Earth revolves around the Sun at a speed of about 18.5 miles/sec (30 km/sec) during this rotation, why the atmospheric wind is not felt by the earth?

 

Earth spins on its axis once in every 24-hour day. At Earth’s equator, the speed of Earth’s spin is about 1,000 miles per hour (1,600 kph). The day-night has carried you around in a grand circle under the stars every day of your life, and yet you don’t feel Earth spinning. Why not? It’s because you and everything else – including Earth’s oceans and atmosphere – are spinning along with the Earth at the same constant speed.

Think about riding in a car or flying in a plane. As long as the ride is going smoothly, you can almost convince yourself you’re not moving. A jumbo jet flies at about 500 miles per hour (about 800 km per hour), or about half as fast as the Earth spins at its equator. But, while you’re riding on that jet, if you close your eyes, you don’t feel like you’re moving at all. And when the flight attendant comes by and pours coffee into your cup, the coffee doesn’t fly to the back of the plane. That’s because the coffee, the cup and you are all moving at the same rate as the plane.

Likewise, Earth is moving at a fixed rate, and we’re all moving along with it, and that’s why we don’t feel Earth’s spin. If Earth’s spin were suddenly to speed up or slow down, you would definitely feel it.

The constant spin of the Earth had our ancestors pretty confused about the true nature of the cosmos. They noticed that the stars, and the sun and the moon, all appeared to move above the Earth. Because they couldn’t feel Earth move, they logically interpreted this observation to mean that Earth was stationary and “the heavens” moved above us.

With the notable exception of the early Greek scientist Aristarchus, who first proposed a heliocentric (sun-centered) model of the universe hundreds of years B.C.E., the world’s great thinkers upheld the geocentric (Earth-centered) idea of the cosmos for many centuries.

It wasn’t until the 16th Century that the heliocentric model of Copernicus began to be discussed and understood. While not without errors, Copernicus’ model eventually convinced the world that Earth spun on its axis beneath the stars … and also moved in orbit around the sun.

Bottom line: Why don’t we feel Earth rotating, or spinning, on its axis? It’s because Earth spins steadily – and moves at a constant rate in orbit around the sun – carrying you as a passenger right along with it.

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