Question

if the kinetic energy of a body is twice it's rest mass energy find its velocity

Answer 1

it's velocity will remain constant

Kinetic Energy = ke

velocity =v

mass =m

$ke = \frac{1}{2} m {v}^{2}$

$2(ke) = 2( \frac{1}{2} m {v}^{2} ) \\ \\ 2ke = m {v}^{2}$

Answer 2

The velocity of the object when its kinetic energy is 2 times its rest mass is 2 m/s.

Given:
Kinetic energy of the body is twice its mass

To find:

The velocity f the object.

Solution:

The kinetic energy of a body is the energy possessed by the body by virtue of its velocity.

Mathematically, Kinetic energy is expressed as

                     $KE=\frac{1}{2} mv^{2}$

Now, according to the question, we have been given that the kinetic energy of the body is twice its rest mass that is

$K=2$ × $m$

Substituting this value in the given equation, we get

$2m=\frac{1}{2} mv^{2}$

$v^{2} =4$

$v=2m/s$

Final answer:

Hence, the velocity of the object when its kinetic energy is 2 times its rest mass is 2 m/s.