Question

How much is the mass of a man if he has to do 2500 J work in climbing a tree 5 m tall. (Take g =10m/s^2)

Answer 1

P.E. = m × g × h

2500 = x × 10m/s^2 × 5 m

2500 = 50m^2/s^2

2500/50 = 50 kg

Answer 2

What energy does/will the man posses?

In the question, its mentioned that there will be change in the mans position or shape. Therefore, the energy posessed by him is Potential Energy.

Potential energy is the energy possesed by a body, due to its change in position or shape.

Potential energy is further classified into Elastic Potential Energy and Gravitational Potential Energy.

Given

Mass of the man = ?

Potential Energy = 2500J

Height = 5m

g = 10 ms - ¹

Solution

We know that the formula to find Potential energy is

Ep = mgh

No we apply the given values in this equation.

2500J = m × 10 × 5

2500J = 50m

$\mathsf{\frac{2500}{50}}$ = m

$\large\boxed{\huge{\mathbf{m = 50}}}}}$

Hence, The mass of the man if he has to do climbing work on a tree 5m tall is 50.