A free pith-ball of $8 g$ carries a positive charge of $5 \times 10^{- 8} C$ . What must be the nature and magnitude of charge that should be given to a second pith-ball fixed $5 c m$ vertically below the former pith-ball so that the upper pith-ball is stationary?

Open in App

Solution

To keep the first pith ball stationary, the net force acting on it should cancel out to be zero.
The force of gravity acting downward $= M g = \frac{8 \times 10}{1000} = 0.08 N$
So, this should be the force acting on it along the upward direction due to other charged pith ball.
Hence, the pith ball placed vertically downward should exert a repulsive force on the first pith ball.

$F = 0.08 N = \frac{9 \times 10^{9} \times 5 \times 10^{- 8} \times q}{(0.05)^{2}}$
Hence, $q = 4.4 \times 10^{- 7} C$

Suggest Corrections

Similar questions

Q. A pith ball of mass

9 \times 10^{- 5} k g

carries a charge of 5

μ C

. What must be charge on another pith ball placed directly 2 cm above the pith ball such that they are held in equilibrium?

A freei pitch ball of mass 6 gram carries a positive charge of (1/3 )* 10 ^-7 coulomb what must be nature and magnitude of charge that should be given to second pitch ball fixed 5 cm vertically below the former baseball so that the upper bonus stationery.

Q. 10^{6 electrons are added to a pith ball. The charge on the pith ball will be.......?}

Q. 10

^{6}

electrons are taken out of a pith ball. The positive charge on the pith ball is

Q. A positively charged body, when brought close to a positively charged pith ball electroscope, would make the pith ball move away from it.

Join BYJU'S Learning Program

A free pith-ball of 8 g carries a positive charge of 5×10−8C. What must be the nature and magnitude of charge that should be given to a second pith-ball fixed 5 cm vertically below the former pith-ball so that the upper pith-ball is stationary?

A free pith-ball of $8 g$ carries a positive charge of $5 \times 10^{- 8} C$ . What must be the nature and magnitude of charge that should be given to a second pith-ball fixed $5 c m$ vertically below the former pith-ball so that the upper pith-ball is stationary?