If a man moves a large box that weighs 10 newtons 120 meters in 1 minute, how much power was used?

Question

 Need help with science word problems

Answer 1

Power = unit of work/unit of time

 

First, we need to determine the amount of work performed by the man.

 

Work = force x distance

 

The force exerted is 10 N

 

The distance is 120 m

 

Therefore, the amount of work = 10 * 120 = 1200 newton-meters

 

You should now be able to find the amount of power used by the man, Sarah

Answer 2

Another way to answer this, using 

 

Power = (applied force) x (speed)

 

P = Fv

 

F = applied force = 10 N

 

Use average speed = (distance traveled) / (length of time interval)

 

v = (120 m) / (60 s) = 2 m/s

 

P = Fv = (10 N)(2 m/s) = 20 watts

 

The answer is the same, just another way to work the problem.  Note the formula Michael gave you is equivalent to using Fv.

 

P = W/t = (Fd)/t = F(d/t) = Fv