Question

define kinetic energy and derive an expression for the kinetic energy of mass m moving with velocity v ​

Answer 1

Explanation:

The energy possessed by an object because of its motion is called kinetic energy.

If a body of mass m is moving with velocity v,its kinetic energy is expressed as follows:

Kinetic energy (KE)=1/2×mv^2

Answer 2

Answer:-

Kinetic energy:-

Kinetic energy is the capacity of a body to do work by virtue of its motion.

Expression for Kinetic energy.

Suppose a Force 'F' acting on a body of mass 'm' from rest moves with a velocity 'v' and body covers a distance 's'.

Now,

Work done = F.s

$w = ma.s \: \: - - - - - (1)$

Now, third equation of motion

${v}^{2} - {u}^{2} = 2as$

u = 0.

${v}^{2} = 2as$

$as = \frac{ {v}^{2} }{2}$

substituting the a.s value in equation (1).

$w = m \times \frac{ {v}^{2} }{2}$

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

Now,

$K.E = \frac{1}{2} m {v}^{2}$

$\boxed{\boxed{K.E = \frac{1}{2} m {v}^{2}}}$

Hence Derived