Question

what is the kinetic energy of a toy truck with a mass of 0.75 kg and a velocity of 4 m/s? (formula: $ke = \frac{1}{2}mv^2$)
○ 3 j
○ 6 j
○ 12 j
○ 24 j

Explanation:

Step1: Identify given values

Mass \( m = 0.75 \, \text{kg} \), velocity \( v = 4 \, \text{m/s} \), and the formula for kinetic energy \( KE=\frac{1}{2}mv^2 \).

Step2: Substitute values into the formula

First, calculate \( v^2 \): \( v^2=(4)^2 = 16 \). Then substitute \( m = 0.75 \) and \( v^2 = 16 \) into the formula: \( KE=\frac{1}{2}\times0.75\times16 \).

Step3: Perform the calculation

\(\frac{1}{2}\times0.75\times16 = 0.5\times0.75\times16\). First, \( 0.5\times16 = 8 \), then \( 8\times0.75 = 6 \).

Answer:

B. 6 J