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 dropdown work than sandra. blakes power is dropdown than sandras power. (hint: use (w = fd) and (p=\frac{w}{t}).)

Explanation:

Step1: Calculate Blake's work

Use the formula $W = Fd$. Blake drags 3 boxes, with $F = 20$ N and $d=10$ m for each box. So $W_{Blake}=3\times F\times d=3\times20\times10 = 600$ J.

Step2: Calculate Sandra's work

Sandra drags 4 boxes, with $F = 15$ N and $d = 12$ m for each box. So $W_{Sandra}=4\times F\times d=4\times15\times12=720$ J.

Step3: Calculate Blake's power

Use the formula $P=\frac{W}{t}$. Blake takes $t = 2$ minutes $= 2\times60 = 120$ s. So $P_{Blake}=\frac{W_{Blake}}{t}=\frac{600}{120}=5$ W.

Step4: Calculate Sandra's power

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

Answer:

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