A man standing on a platform holds weight in his out stretched arms. The system rotates freely about a central vertical axis. If he now draws the weights inwards close to his body. 1) the angular velocity of the system will decrease 2) the angular momentum of the system will decrease. 3) the kinetic energy of the system will increase 4) he will have to expend some energy to draw the weights in Which of the following is correct?

Question

a) 2, 3

b) 1, 2

c) 3,4

d) 1,4