Question

The magnitude of Kinetic energy of a body is 'K'. What is its kinetic energy if its velocity is doubled ?​

Answer 1

Given:

The magnitude of Kinetic energy of a body is 'K'.

To find:

Kinetic Energy when velocity doubles?

Calculation:

• Let initial velocity be v , so initial KINETIC ENERGY will be :

$KE = \dfrac{1}{2} m {v}^{2}$

• Now, new velocity is double as that of initial velocity. So, v_(2) = 2v.

• New kinetic energy will be :

$KE_{2}= \dfrac{1}{2} m {(2v)}^{2}$

$\implies KE_{2}=4 \times \dfrac{1}{2} m {v}^{2}$

$\implies KE_{2}=4 ( KE)$

So , new kinetic energy is 4 times the initial kinetic energy.

Answer 2

Answer:

If the velocity of a body is doubled , the resulting kinetic energy is four times of the initial kinetic energy.

Explanation:

Kinetic energy : It is the energy possessed by the body due to its motion. If a body is at rest ,its kinetic energy wil be zero.

• The magnitude of the kinetic energy of a body depends on its velocity. Higher the velocity, greater will be the kinetic energy and lower the velocity , lesser will be the kinetic energy.

         Formula of Kinetic energy:

                      K.E. =  1/2 m v2

If velocity is doubled,

Let initial velocity = v,

when doubled , final velocity = 2v,

Then Kinetic energy will be four times of initial value.