Question

if a 82 kg person is in an elevator moving at a speed of 5 m/s, then what is the persons kinetic energy?
a 82 j
b 5 j
c 410 j
d 1,025 j

Explanation:

Step1: Write the formula for kinetic energy

The formula for kinetic energy is \(K.E.=\frac{1}{2}mv^{2}\), where \(m\) is the mass and \(v\) is the velocity.

Step2: Substitute the given values

Given \(m = 82\space kg\) and \(v=5\space m/s\). Substitute into the formula: \(K.E.=\frac{1}{2}\times82\times(5)^{2}\)
First calculate \((5)^{2}=25\), then \(\frac{1}{2}\times82 = 41\), and \(41\times25=1025\)

Answer:

D. \(1025\space J\)