Question

• A ball of mass 0.5 kg slows down from a speed of
5 ms-' to that of 3 m 5-1. Calculate the change in
the kinetic energy of the ball.
Ans. 4 J (decrease)​

Answer 1

Answer:

4 J

Explanation:

Initial Kinetic Energy KE

i

=0.5×m×v

1

2

Final Kinetic Energy K.E

f

=0.5×m×v

2

2

KE

difference

=KE

f

−KE

i

KE

difference

=

2

1

×0.5(3×3−5×5)

KE

difference

=

4

1

(9−25)

KE

difference

=

4

−16

=−4J

Hence kinetic energy will get reduced by 4J