# physics

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a 200 kg block was moved along an inclined plane to a height of 10m. during this process 3000J of energy was lost due to friction.

a. calculate the efficiency of the inclined plane.

b. what would the efficiency of the simple machine be if the incline were frictionless?

c. how would the efficiency of the inclined plane change (decrease or increase or no change) if the incline were longer with no change in height? Hint: consider change of work due to friction.

please explain more than just giving me an equation.

• physics - ,

a) The efficiency is the increase in potential energy that results (Weight x height change), divided by the work that had to be done.

b) 100%

c) With a less steep ramp angle, the friction force goes up while the distance needed to push the block also goes up. The work done against gravity strays the same. This increases the work required. What does that do to the effciciency ratio (P.E. change)/Work ?

• physics - ,

a. how do i encorporate the 3000J of lost energy?

• physics - ,

Add the friction work to the work done against gravity, M g H, to get the total work required. (in part a)

• physics - ,

i still don't understand how you put that into the formula