Rankers Physics

Gauss's Law: Practice Problem & Solution

A charge $q$ is placed in an uniform electric field $E$. If it is released, then the K.E. of the charge after travelling distance $y$ will be: (1998)
$qEy$
$2qEy$
$\frac{qEy}{2}$
$\sqrt{qEy}$

Solution Explained:

To solve this problem, we apply the core principles of Gauss's Law. Understanding the underlying formula is key to arriving at the correct answer below:

The force experienced by the charge is $F = qE$. The work done by this force in moving the charge through a distance $y$ is $W = F \times y = qEy$. According to the work-energy theorem, this work done is equal to the kinetic energy acquired, so K.E. = $qEy$.

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