To determine the power Carter uses while pushing the bag, we need to follow these steps:
1. Calculate the Work Done:
Work done [tex]\( W \)[/tex] is given by the formula:
[tex]\[
W = F \times d
\][/tex]
where [tex]\( F \)[/tex] is the force applied and [tex]\( d \)[/tex] is the distance over which the force is applied.
Given:
- [tex]\( F = 21 \)[/tex] newtons
- [tex]\( d = 9 \)[/tex] meters
[tex]\[
W = 21 \ \text{N} \times 9 \ \text{m} = 189 \ \text{Joules}
\][/tex]
2. Calculate the Power:
Power [tex]\( P \)[/tex] is given by the formula:
[tex]\[
P = \frac{W}{t}
\][/tex]
where [tex]\( t \)[/tex] is the time in seconds over which the work is done.
Given:
- [tex]\( W = 189 \)[/tex] Joules (from step 1)
- [tex]\( t = 3 \)[/tex] seconds
[tex]\[
P = \frac{189 \ \text{J}}{3 \ \text{s}} = 63 \ \text{watts}
\][/tex]
So, Carter uses 63 watts of power.
Answer:
D. 63 watts
