Select the word from the list that best fits the definition

equals the output work divided by the input work

a) input force
b) efficiency
c) mechanical advantage
d) output force
e) compound machine

the answer is B) efficiency

Explanation:

C) efficiency

Explanation

Efficiency is a measure of the ability to save resources or not wasting them. Generally, in a machine, mathematically, efficiency id defined as output power (or work) divided by input power (or work).

A) Input force: this is not the right answer because here we're talking about work (no forces).

B) efficiency: This is the word more similar to the definition. More specifically, in this case, we're talking about mechanical efficiency.

C) mechanical advantage is a measure of force amplification (output force divided by input force) and not output work divided by the input work.

D) Output force: this is not the right answer because here we're talking about work (no forces).

E) compound machine: it's just a type of machine, not a ratio of works.

b.a device that inputs heat into a cool object