Question

2.1.2 quiz: types of energy
question 7 of 10
you launch a model rocket that has a mass of 2 kg. at a height of 400 m, it is traveling at 150 m/s. what is its kinetic energy at this point?

a. 113 j
b. 150 j
c. 45,000 j
d. 22,500 j

Explanation:

Step1: Recall kinetic energy formula

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

Step2: Identify given values

Mass $m = 2\space kg$, velocity $v = 150\space m/s$.

Step3: Substitute values into formula

Substitute $m = 2$ and $v = 150$ into $KE=\frac{1}{2}mv^2$:
$$KE=\frac{1}{2}\times2\times(150)^2$$
First, $\frac{1}{2}\times2 = 1$. Then, $(150)^2=22500$. So $KE = 1\times22500 = 22500\space J$.

Answer:

D. 22,500 J