Question

Formula help Can someone help me find the right formula for these two question....i dont want the answer just help with the formula

Paco rode his skateboard up a ramp for a distance of 3.8 meters. If the ideal mechanical advantage of the ramp is 2, how far above the ground was Paco?

I think it is 3.8 x 2 = ? but i am unsure

Lucas has been challenged to increase the efficiency of a device he is redesigning. His goal is 90 percent efficiency. The work input of the device is fixed at 10 joules, so Lucas is trying to improve work out

Answer 1

second one i think is 90 x 10 = Output

Answer 2

See
http://interactagram.com/physics/dynamics/MechanicalAdvantage/ramp/
for a picture of what mechanical advantage of a ramp means.

Answer 3

the mechanical advantage of a ramp is "distance up" divided by the length of the ramp