Question

Lucy needs to lift a crate to a shelf 20 m high. She does 12,000 J of work on a machine to help her. The machine exerts a force of 500 N to lift the crate.

Answer 1

Answer:

83.34%.

Explanation:

Given that,

Lucy does 12,000 J of work on a machine to help her

The machine exerts a force of 500 N to lift the crate.

Height of the shelf = 20 m

We need to find the efficiency of the machine. The ratio of output work to the input work is called the efficiency of any machine. It is given by :

$\eta=\dfrac{W_o}{W_i}\times 100\\\\=\dfrac{500\times 20}{12000}\\\\=83.34\%$

So, the efficiency of the machine is 83.34%.

Answer 2

Answer:

83%

Explanation:

just took quiz on connections acadmy