A child pulls on a wagon with a force of 75${~N}$ If the wagon moves a total of $42 \mathrm {~m}$ in $3.1 \mathrm {~min} \text {, }$ what is the average power delivered by the child?
A) 17 W
B) 21 W
C) 22 W
D) 26 W

Question

A child pulls on a wagon with a force of  75${~N}$ If the wagon moves a total of $42 \mathrm {~m}$ in $3.1 \mathrm {~min} \text {, }$ what is the average power delivered by the child?
A) 17 W
B) 21 W
C) 22 W
D) 26 W

Quizplus · Accepted Answer

Power is calculated as work done over time. Work done is force times distance, so $75 \, \text{N} \times 42 \, \text{m} = 3150 \, \text{J}$. Time is $3.1 \, \text{min} = 186 \, \text{s}$. Power = $3150 \, \text{J} / 186 \, \text{s} \approx 16.94 \, \text{W}$, which rounds to 17 W.

A Child Pulls on a Wagon with a Force of N{~N} N

A Child Pulls on a Wagon with a Force of ${~N}$