Question Detail

PHY 102 ELECTROSTATICS Objective Question

Question

If a charge q accelerates from rest due to a potential difference V, its final kinetic energy (1/2 mv2) is equivalent to:
Options
A <i>qV</i>.
Correct Answer
B <i>q/V</i>.
C <i>mV</i>.
D <i>qE</i>.
Correct Answer

Option A is the correct answer.

Detailed Explanation

Page 19, equation 3.14, shows the relationship 1/2 mvA² - 1/2 mvB² = q(VB - VA). If starting from rest (mvA² = 0) and V = (VA - VB) (as implied by acceleration of positive charge from higher to lower potential, or V = (VB - VA) for negative q and acceleration), then 1/2 mvB² = qV. Page 20 explicitly uses qV = 1/2 mv² in the example.

Hint

The work done by the electric field (or by potential difference) is converted into kinetic energy. Check the example on page 20.

Question Info