Question

(b) The kinetic energy of an object of mass 'm moving with a velocity
of 10 m/s is 500J
() What will be the kinetic energy, when its velocity is doubled?
(ii) What will be its Kinetic energy when its velocity is reduced to halt?​

Answer 1

Answer:

1. When it's velocity is doubled, it's kinetic energy will be 1000J

3. When velocity is halved, it's k.e will be 10/8

Answer 2

Answer:

First let's find the mass

$Since,KE= \frac{1}{2} m {v}^{2}$

$500 = \frac{1}{2} \times m \times {10}^{2}$

500=100m

m=500/100

m=5kg

Condition 1:

velocity=20m/s(doubled)

Now,

KE=1/2mv^2

=1/2×5×20^2

=1/2×5×400

=1000J

Condition 2:

velocity=5m/s(halved)

KE=1/2mv^2

=1/2×5×5^2

=1/2×5×25

=62.5J