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# Tag Archives: energy

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## Can the frictional electricity produced during landing of a plane be used for constructive purposes?

As we know that in aeroplane during landing the charged produced in it due to the friction with ground are earthed through its wheels; can this charge be stored with the help of a capacitor and used for useful purpose?

I feel that this is a metter for research.

If you feel otherwise and know some method to tap this potential, please post.

## Doubts on electric field lines and flux

Q1.Is the number of electric feild lines due to a charge DEFINITE?
Q2.If it is infinite, then the electric flux due to a charge should be infinite(flux gives the num. Of elctric feild lines passing through an area)?
AND
Flux should be equal irrespective of the magnitude of charge.
Q3.If it is definite,then it will always be a natural number and cannot be a decimal,but when we take out flux for an Electron,it yeilds a decimal value.
E.flux~ magn. Of charge
————————
Permittivity of Medium
Medium-taken to be vaccum(here).

Mathar Hasan posted

## What is the mechanical energy of a bird on top of a moving Ship?

A bird is at rest on d top of a stick of moving ship….!! what is the mechanical energy that exists in the bird ???” – This question was posted by Fatima

Answer: The mechanical energy of the bird is both Potential and Kinetic as the bird is at a height with respect to ground and the bird is in motion along with the ship.

(Any deeper discussion is welcome)

## A bullet of mass 20g enters into a fixed block with aspeed 40m/s and stops in it. find the change in internal energy during the process.

A bullet of mass 20 g enters into a fixed block with a speed 40m/s and stops in it.
find the change in internal energy during the process?

The question is open to visitors to post answer as comment

## Differences between mass and charge

1. Charge is of two types, mass is only of one kind
2. There are two types of forces (attraction and repulsion) between charges, but there is only one kind (attraction) between masses
3. Charge is quantized, but quantization of mass is not established so far
4. Charge has SI unit coulomb, the SI unit of mass is kg
5. Charge is conserved, but mass alone is not conserved (Mass + Energy is conserved)
6. Charge cannot exist without a mass, but mass can exist without a net charge

(… Try finding out more)

## Geothermal Energy

“Why is geothermal energy an alternative source of nuclear energy?”

There is some problem with the doubt you asked. It is correct to say “Geothermal energy and Nuclear energy are alternative sources of energy

Sun is the ultimate source of energy for earth. The energy of fuels, wind energy, water energy, food – all these are derived from sun. But Geothermal energy and nuclear energy are not derived from solar energy.

http://www.renewableenergyworld.com/rea/tech/geothermal-energy

http://www.geos.iitb.ac.in/geothermalindia/pubs/geoweb.htm

See a diagram of Geothermal plant

The centre of the Earth is around 6000 degrees Celsius – easily hot enough to melt rock. Even a few kilometres down, the temperature can be over 250 degrees Celsius if the Earth’s crust is thin. In general, the temperature rises one degree Celsius for every 30 – 50 metres you go down, but this does vary depending on location

In volcanic areas, molten rock can be very close to the surface. Sometimes we can use that heat.

Geothermal energy has been used for thousands of years in some countries for cooking and heating.

The name “geothermal” comes from two Greek words: “geo” means “Earth” and “thermal” means “heat”.

Read More on Geothermal Energy Here

## Waking up the quantum vacuum

A quantum ﬁeld propagating in a curved spacetime can have ﬂuctuations in its vacuum energy density that are large enough to completely dominate its classical energy density.

Published Mon May 03, 2010

Go here to see the original: Waking up the quantum vacuum