Rankers Physics

Photoelectric Effects and deBroglie Equation: Practice Problem & Solution

The kinetic energy of an electron, which is accelerated in the potential difference of 100 volts, is (1997)
$416.6 cal$
$6.636 cal$
$1.602 \times 10^{-17} J$
$1.6 \times 10^4 J$

Solution Explained:

To solve this problem, we apply the core principles of Photoelectric Effects and deBroglie Equation. Understanding the underlying formula is key to arriving at the correct answer below:

Kinetic energy acquired by an electron accelerated through a potential difference V is $K.E. = eV$. Here $V = 100 V$, so $K.E. = (1.602 \times 10^{-19} C) \times 100 V = 1.602 \times 10^{-17} J$.

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