Home
Class 12
PHYSICS
A conducting bolloon of the radius a is ...

A conducting bolloon of the radius a is charged to potential `V_(0)` and held at a large height above the earth ensures that charge distribution on the surface of the balloon remains unaffected by the presence of the earth. It is connected to the earth through a resistance R and a value in the balloon is opened . The gas inside the balloon escapes from value and the size of the balloon decreases. The rate of decrease in radius of the balloon is controlled in such a manner that potential of the balloon remains constant. Assume the electric permittivity of the surrounding air equals to that of free space `(epsilon_(0))` and charge cannot leak to the surrounding air.

The rate at which radius r of the balloon changes with time is best represented by the equation

A

`(dr)/(dt)=(1)/(4piepsilon_(0)R)`

B

`(dr)/(dt)=-(1)/(4pi epsilon_(0)R)`

C

`(dr)/(dt)=(1)/(4pi epsilon_(0)aR)`

D

`(dr)/(dt)=-(r)/(4pi epsilon_(0)aR)`

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Similar Questions

Explore conceptually related problems

The value of escape speed from the surface of earth is

If V is the gravitational potential on the surface of the earth, then what is its value at the centre of the earth ?

The height above the earth s surface at which the weight of a person becomes 1/4th of his weight on the surface of earth is (R is the radius of earth)

A rubber balloon is given a charge Q distributed uniformly over its surface. Then

A man weighs 'W' on the surface of the earth and his weight at a height 'R' from surface of the earth is ( R is Radius of the earth )

At what height above the earth's surface does the value of g becomes 36% of the value at the surface of earth ?

The height above the surface of earth at which the gravitational filed intensity is reduced to 1% of its value on the surface of earth is

At what height above the earth's surface the acceleration due to gravity will be 1/9 th of its value at the earth’s surface? Radius of earth is 6400 km.

At what height above the surface of earth the value of "g" decreases by 2 % [ radius of the earth is 6400 km ]

The height from the surface of earth at which the gravitational potential energy of a ball of mass m is half of that at the centre of earth is (where R is the radius of earth)