Question

select the correct answer. carter pushes a bag full of basketball jerseys across the gym floor. then he pushes with a constant force of 21 newtons. if he pushes the bag meters in 3 seconds, how much power does he use? (hint: 1 watt = 1 $\frac{ncdot m}{s}$) a. 3 watts b. 7 watts c. 27 watts d. 63 watts e. 189 watts

Explanation:

Step1: Recall power formula

Power $P=\frac{W}{t}$, and work $W = F\times d$. Here we assume the distance is 9 meters (distance value missing in question but for calculation purposes, if we assume a value to show the process. Let's assume the distance $d = 9$ meters). First, calculate work $W$.
$W=F\times d=21\times9 = 189$ joules

Step2: Calculate power

$P=\frac{W}{t}$, with $W = 189$ joules and $t = 3$ seconds.
$P=\frac{189}{3}=63$ watts

Answer:

D. 63 watts