Question

A foam ball of mass 0.150 g carries a charge of -2.00 nC. The ball is placed inside a uniform electric field, and is suspended against the force of gravity. What are the magnitude and direction of the electric field?

Answer 1

Answer:

Electric field, $E=-7.35\times 10^5\ N/C$ in the direction of gravity.

Explanation:

Given that,

Mass of the ball, m = 0.15 g

Charge on the ball, $q=-2\ nC=-2\times 10^{-9}\ C$

The ball is placed inside a uniform electric field, and is suspended against the force of gravity such that,

$mg=qE$

$E=\dfrac{mg}{q}$

$E=\dfrac{0.15\times 10^{-3}\times 9.8}{-2\times 10^{-9}}$

$E=-7.35\times 10^5\ N/C$

The electric field will be acting in the direction of gravity. Hence, this is the required solution.