Topic: Comets.
Why do comets have tails?
Maybe because, like monkeys, they can hang themselves on trees.
No.
Let me explain.
A comet is a mixture of rocks, dust and ice.
This ice is basically frozen water and frozen gases.
When a comet approaches the sun, it starts to heat up converting ice directly into gas.
Releasing the trapped dust particles in space.
So, you mean a comet has two tails.
Absolutely.
Stop bluffing.
No.
It is true.
The ultraviolet radiations from the sun ionize the gas and the solar wind carries this ionized gas away from the sun, forming an ion tail.
Whereas, the light from the sun exerts pressure on the dust particles and pushes them away, creating a dust tail.
Topic: Lateral Inversion.
Why is ambulance written in reverse?
Maybe because there is some secret code hidden in it.
You're just impossible.
It is because mirrors form laterally inverted images.
Lateral inversion is a phenomenon due to which the left side of an object appears to be the right side in the mirror.
The right side appears to be the left side.
Which hand are you raising now?
Ok, Don't get angry.
Let's get back to the question.
We know that ambulance is an emergency vehicle.
Hence, when the driver of the front vehicle will see the ambulance in the rear-view mirror.
He will see the laterally inverted image of the word and thus read it correctly, giving way to the ambulance.
Topic: Osmosis.
How do fish drink water?
That's easy.
Using a straw.
No.
Fish take in water usually through their mouth or gills, depending on whether they live in freshwater or saltwater.
Freshwater fish takes in water mainly through its gills.
But Why?
Because it has less water and more salt concentration in its blood than the surrounding water.
Hence, due to osmosis, water from the surrounding flows through the gills into its bloodstream.
However, as the fish is continuously taking in water, it urinates a lot and removes excess water.
Saltwater fish takes in water through its mouth.
Really.
This is because its blood has more water and less salt concentration than the saltwater around it.
Hence, to maintain the balance, the fish gulps saltwater through its mouth, filters the water for its use and expels excess salt while urinating.
Topic: Gravity.
Why are planets round?
Because I commanded them.
You wish.
Planets are round because of the force of gravity.
Gravity acts as if it originates from the center of a planet and pulls each point of the planet towards it.
Hence, the only way for everything on the surface to be equally close to its center is to form a round shape.
However, planets are not exactly round.
They are roughly spherical.
This is because planets spin on their axes.
Just like a spinning top, right?
Absolutely.
When planets spin, things near the equator tend to move away from the center due to centrifugal force.
Resulting in formation of an equatorial bulge.
Because of this bulge, the equator of a planet becomes farther from its center than its poles, creating a roughly spherical planet.
Topic: Convex lens.
Can a magnifying glass burn paper?
I think you have gone nuts.
No.
It is possible.
What?
But how?
It is because a magnifying glass is actually a convex lens.
A convex lens is thicker in the middle and thinner at the edges.
Like a fish?
Absolutely.
This shape of the convex lens makes the parallel rays of sunlight to refract such that they converge or come together at a point.
So, when they come together, do they have a party?
Please listen.
As the rays converge, the concentration of sunlight at that point increases, thus producing heat.
This heat starts a fire which eventually causes the paper to burn.
Topic: Atmospheric refraction.
Why do stars twinkle?
Because they blink their eyes.
No.
The twinkling of stars is due to atmospheric refraction.
Atmospheric refraction is the bending of light caused by the earth's atmosphere.
I thought atmospheric refraction is the bending of my body due to earth's atmosphere.
Please listen.
Earth's atmosphere is changing continuously.
When the light of a star travels through space towards us.
The continuously changing earth's atmosphere refracts or bends the light by different amounts and in different directions every moment.
When the atmosphere refracts more starlight towards us, the star appears bright.
When the atmosphere refracts less starlight, the star appears dim.
In this way, the amount of starlight reaching our eyes increases and decreases causing the star to appear twinkling.
Topic: Surface Tension.
Why are drops spherical?
Because personally, I am fond of spherical shapes as compared to squares.
No.
It is because of surface tension.
Surface tension is the property of liquids by which surface molecules of a liquid try to hold the liquid together by acquiring minimum surface area.
Acting like a stretched membrane.
You know what, everything just went over my head.
Alright.
I will explain.
Inside a drop, each water molecule is pulled with a force by its neighboring molecules.
As these forces are equal and opposite, they get neutralized.
However, the molecule present at the surface is not attracted outwards.
It is attracted only inwards and sideways.
Sideways forces get neutralized.
But because of the inward force, each surface molecule contracts to form a shape that has minimum surface area which is a sphere
Topic: Water Purification.
Why is alum added to water?
Because water does not like to be alone.
It wants somebody's company.
No.
Alum is added to purify water.
Alum is aluminium sulfate.
It acts as a coagulant.
A coagulant attracts and binds with extremely fine and small particles to form a large particle.
I won't use it.
But why?
Because it will attract all small insects and make a large insect.
You are just unbelievable.
When a solution of alum is added to impure water.
It attracts and binds with contaminants and fine suspended particles of mud, dirt, etc. to form large particles.
Being large, these particles can be removed by filtration, or when they settle down due to gravity.
They can be removed through decantation, giving us pure water.
Topic: Resonance.
How does sound break glass?
Obviously, using a hammer.
No.
It is because of resonance.
I know.
Resonance means to keep calm and balance.
No.
Wait, I will explain.
Every object when struck vibrates at its natural frequency.
If we make sound having a frequency which matches the object's natural frequency.
Then that object starts to vibrate.
This phenomenon is called resonance.
So, this was the reason why my legs started to move when the music system was switched on.
Just listen.
Every glass is made up of different materials.
However, all of them have a natural resonant frequency.
Hence, when we make sounds which match their resonant frequencies, the glasses start to vibrate.
As glass is a brittle material, louder the sound, more violently will it vibrate causing the glass to shatter into pieces.
Topic: Properties of a liquid.
Why is a diver able to cut through water in a swimming pool?
Simple.
Because I taught him.
No.
This is because of intermolecular force.
Intermolecular force is the force of attraction present in between the molecules of solids, liquids or gases.
Now, the Intermolecular forces in liquids are not very strong.
This means I am the strongest of all.
Please listen.
Since the intermolecular forces are not strong, the molecules of a liquid are loosely packed.
They have empty spaces in between them.
As a result, the molecules can be displaced from their original position.
Hence, when a diver jumps into water, its molecules get displaced from their original position and the diver is able to cut through the water.