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Traveling in a flight from say India to USA

If I have to travel from India to the USA, I take flight. The flight flies and keeps traveling towards USA for about say 17 hours. Why does it kepps travelling? If it flies and stays still for the hours we assume USA to be behind India time, will it land there and reach USA? If no why?

United (States) Parcel Service.


Asked Ashwini Joshi

Pressure, Thrust, Area and Pascal’s Law

“In Pascal’s law we find that pressure does not increase with area. But when we study about pressure, we learn that pressure is inversely proportional to area. How is this possible? Please explain.”

Fahad Imtiaz asked via Speak Pipe



Pressure is defined as the thrust (the total force acting normal to a surface) per unit area.

Pascal’s law deals with fluid pressure and the statement goes –

“The pressure exerted anywhere in an enclosed incompressible and non-viscous fluid is transmitted equally and undiminished in all directions through out the fluid, provided the effect of gravity is neglected”

Read the statement carefully.

Here we are not changing the definition or meaning of pressure.

the fact to note that, in an enclosed fluid, the pressure is transmitted equally throughout the fluid. Therefore, if we apply some pressure somewhere in the fluid, the same pressure will be felt  at any other place on the enclosed fluid. This gives us an opportunity to multiply the force. Since the pressure is equal everywhere, if we increase the area the force (thrust) is increased.

P = F/A or F = PA

So, pressure remaining constant, greater the area, greater is the force.

Hope you understand the matter now.

The countdown has begun, Start revising for the board exams!

Only a few days left before the board exams begin. Have you revised well?

Class XI Physics NCERT Exercise 9.19 solution







What is the full form of LED?

What is the full form of LED television and also AMOLED?
and which is better and why?

Asks Dipak Kumar

Answer: LED stands for Light Emitting Diode.

LED TVs are actually LED backlit LCD TVs.
Instead of fluorescent tubes, LEDs shine light from behind the screen, illuminating the pixels to create an image. Due to the small size and low power consumption of LEDs, LED-backlit TVs are far thinner than regular LCD sets and are also more energy efficient. They can also provide a (more…)

Are we creating a universe when we explode a nuclear bomb?

The big bang theory claims an explosion formed the universe.  Therefore we are living inside of an explosion.  However an explosion as we experience it is almost an instantaneous thing. To an observer outside the universe it would be over rather quickly.  Yet we perceive it as billions of years.

Are we creating a universe when we explode a nuclear bomb?

Answer: We are not creating universe by bomb explosion – but destructing it.

Explosion (Photo credit: gynti_46)

The big Bang is referred to as an explosion  because of the fast expansion it caused.

English: Shows slices of expansion of universe...
English: Shows slices of expansion of universe without an initial singularity (Photo credit: Wikipedia)
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