Question

find the change in Kinetic energy if
momentum increases by
20%​

Answer 1

Explanation:

The relation between kinetic energy and momentum is

KE=

2m

p

2

........(1) Where, p is the momentum

When momentum is increases by 20%, new momentum is p

′

p

′

=p+0.2p

p

′

=1.2p

New kinetic energy

KE

′

=

2m

p

′

2

KE

′

=

2m

(1.2p)

2

KE

′

=

2m

1.44p

2

KE

′

=1.44KE ( from equation 1 )

Change in kinetic energy

ΔKE=

KE

KE

′

−KE

×100

ΔKE=

KE

1.44KE−KE

×100

ΔKE=44%

So, kinetic energy is increased by 44 %

Answer 2

Answer:

So, KE varies as square of the momentum. On 20% increase of p, KE varies as (1.2p)^2 or 1.44p^2. Hence, increase in KE is 44%Explanation: