Bihar Police Constable Model Paper 6

• The correct answer is option 3, i.e., 4 J.
• The kinetic energy of the ball is 4 J.
• The word 'kinesis' means 'motion', thus the energy possessed by an object by virtue of its moving state is termed as Kinetic Energy (K.E).
• The formula for calculating K.E is K.E. = ½ m ${\mathit{v}}^2$
• Here, we are given the mass and velocity of the ball, so we can calculate K.E. using the above formula:

          ⇒ K.E. = ½ x 0.5 x 4 x 4

          ⇒ K.E. = ½ x 2 x 4

          ⇒ K.E. = 4 J