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How far can a mother push a 20.0 kg baby carriage, using a force of 62 N, if she can only do 2920 J of work? Question 3 options: A. 1240 m B. 47.09 m C.146 m D. 3.1 m

Question 4 (20 points) Question 4 Unsaved A force used to lift a 25 kg mass to a height of 12 m in 5 sec does 2100 J of work. How much force is used? Question 4 options: A. 84 N B. 175 N C. 300 N D. 2.08 N

Question 5 (20 points) Question 5 Unsaved A force used to lift a 25 kg mass to a height of 24 m in 5 sec does 2120 J of work. Calculate the power. Question 5 options: A. 600 W B. 424 W C. 84.8 W

2 Answers

4 votes
3: B. 47.09 m

4: B. 175 n

5: B. 424 w

I just did the same test all those are the correct
User GooseSerbus
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7.7k points
6 votes

1) The correct answer is B. 47.09 m


In fact, the work done by the mother is


W=Fd

where F is the force she applied and d is the distance covered by the baby carriage. We are told that the maximum work she can done is
W=2920 J, while the force she applies is F=632 N, therefore by rearranging the previous equation we find the distance travelled by the baby carriage:


d=(W)/(F)=(2920 J)/(62 N)=47.09 m


2) The correct answer is B. 175 N.


As before, the work done is


W=Fd

where F is the force applied and d is the height at which the mass has been lifted. In this case, W=2100 J and d=12 m, therefore the force used is


F=(W)/(d)=(2100 J)/(12 m)=175 N


3) The correct answer is B. 424 W.


The power is the ratio between the work done and the time taken, so we have:


P=(W)/(t)=(2120 J)/(5 s)=424 W

User Dan MacBean
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6.9k points