Question

A weightlifter lifts 250 kg from the ground to a height of 1.5 m in 3.0 s. What is the average power generated by him?

With explanation please
A) 1225 W
B) 125 W
C) 250 W
D) 3675 W

Answer 1

A - 1225W

Step-by-step explanation:

As the weightlifter lifts the object, the object gains gravitational potential energy. Therefore, we will need to calculate how much energy is being used or how much work is being done. You can either use this formula;

Gravitational potential energy (Eₚ) = mgh

or

Work done (E) = F × d

Both of them will give you the same answer!

In my working, I used this formula;

Eₚ = mgh

Eₚ = 250 × 9.8 × 1.5

Eₚ = 3675J

Then, with this energy, we can calculate the power;

P = E/t

P = 3675/3

P = 1225W

I hope this helps! Please let me know any misconceptions or miscalculations and feel free to ask me any questions!