Question

The kinetic energy of an object weighing 10 kg moving with a velocity of 5m/ s is 125J. What is the maximum amount of work that can be done by the object?​

Answer 1

Answer:

The answer is 125J

Explanation:

According to the work-energy theorem, the work done by the sum of all forces acting on a particle is equal to the change in the kinetic energy of the particle. Therefore the maximum work done by an object is equal to its kinetic energy, and hence the answer is 125 J.

Answer 2

Given:

The kinetic energy of an object weighing 10 kg moving with a velocity of 5m/ s is 125J.

To find:

Max work done by force on object ?

Calculation:

Lets assume that the object started from rest and then attained a velocity of 5 m/s over the course of time.

Now, in these kind of questions, its best to apply WORK-ENERGY THEOREM:

• It states that the total work done by all the forces acting on the body is equal to the change in kinetic energy of the object.

$\therefore \sf \: W = \Delta KE$

$\implies\sf \: W_{force} = KE_{2} - KE_{1}$

$\implies\sf \: W_{force} = (\dfrac{1}{2} \times 10 \times {5}^{2} ) - ( \dfrac{1}{2} \times 10 \times {0}^{2} )$

$\implies\sf \: W_{force} = (\dfrac{1}{2} \times 10 \times {5}^{2} ) - (0)$

$\implies\sf \: W_{force} = \dfrac{1}{2} \times 10 \times {5}^{2}$

$\implies\sf \: W_{force} = \dfrac{1}{2} \times 10 \times 25$

$\implies\sf \: W_{force} = 125 \: joule$

So, the net work done by all the forces acting on the body is 125 Joules.