Question

A ramp is often used to raise an object. If 80 joules of energy are needed to lift an object to a platform but 100 joules are used in rolling the object up the ramp, what is the efficiency of the ramp?

Answer 1

efficiency = input/output =80/100j 20 j in friction=20%

Answer 2

Answer:

0.8 or 80%

Explanation:

The amount of energy used in rolling the object up the ramp is 100 joules

the amount of energy used to raise the object  is 80 joules. This means the remaining 20 joules of energy is wasted in form of friction between the object and the ramp.

Therefore efficiency of the ramp = energy utilized/ energy supplied= 80/100

= 0.8= 80%