Question

select the correct answer from each drop - down menu. blake and sandra are having a rummage sale. blake drags 3 boxes a distance of 10 meters each. he exerts a force of 20 newtons on each box. sandra drags 4 boxes a distance of 12 meters each. she exerts a force of 15 newtons on each box. blake takes 2 minutes to complete his work. sandra takes 4 minutes. blake does drop - down work than sandra. blakes power is drop - down than sandras power. (hint: use w = fd and p = \frac{w}{t})

Explanation:

Step1: Calculate Blake's work

For each box, $F = 20$ N and $d=10$ m, and he has 3 boxes. Using $W = Fd$, total work $W_{Blake}=3\times F\times d = 3\times20\times10=600$ J.

Step2: Calculate Sandra's work

For each box, $F = 15$ N and $d = 12$ m, and she has 4 boxes. Using $W = Fd$, total work $W_{Sandra}=4\times F\times d=4\times15\times12 = 720$ J.

Step3: Calculate Blake's power

Blake takes $t_{Blake}=2$ minutes $= 2\times60 = 120$ s. Using $P=\frac{W}{t}$, $P_{Blake}=\frac{W_{Blake}}{t_{Blake}}=\frac{600}{120}=5$ W.

Step4: Calculate Sandra's power

Sandra takes $t_{Sandra}=4$ minutes $=4\times60 = 240$ s. Using $P=\frac{W}{t}$, $P_{Sandra}=\frac{W_{Sandra}}{t_{Sandra}}=\frac{720}{240}=3$ W.

Answer:

Blake does less work than Sandra. Blake's power is greater than Sandra's power.