Question

A foam ball of mass 0.150 gm 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? (g=10ms2)

Answer 1

Answer:

$\diamond \sf \: E = -0.75 \times 10^6$

$\diamond$ The electric field will acts on the direction of gravity.

Explanation:

Given:

• $\sf Mass, m = 0.15 g$

• $\sf q = -2nc = -2 \times 10^{-9} C$

• $\sf g = 10 \: m/s^2$

To Find:

• Magnitude and direction of the electric field.

Solution:

We know that,

$\qquad \quad {\large{\red{\bf mg = qE}}}$

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

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

$\implies \sf E = \dfrac{0.15 \times 10^6 \times 10}{-2}$

$\implies \sf 0.15 \times 10^6 \times (-5)$

$\implies \sf -0.75 \times 10^6$

$\therefore$ The electric field will acts in the direction of gravity.