Doing some physics work and im not sure if what im doing is right. The question is:
On a building site, a 600W electric winch and a pulley were used to lift bricks from the ground. The winch raised a load of 500N through a height of 3.0m in 25s
a) Calculate how much useful energy was transferred by the mortor
i would use the work done equation since energy transferred= work done.
b) calculate the percentage efficiency
Ok, if i am right i would use the answer from a and divide it by the input energy and multiply it by 100 to get my answer.....however how am i supposed to know the input energy?!!? Would i just convert the 600W to joules to use as my input energy?
Am i even close or right?!?!?!
So so sorry for the longgg request!
Thank You! Xxxxx