Aramp 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 percent of energy was wastec in the form of heat due to friction?

20 % of energy is wasted

Explanation:

If 100 joules of energy are used when 80 joules was needed, then 100 - 80 = 20 joules were wasted. Given that 100 joules are proportional to 100 % of energy used, then 20 joules is proportional to x %, therefore:

20 J/100 J = x%/100%

x = 20%

1 - wave length

2 - amplitude

3 - crest

4 - trough

explanation:

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