If a skater of weight 3 kg has initial speed 32 m / s and second one of weight 4 kg has 5 m / s . After collision, they have speed (couple) 5 m / s . Then the loss in K.E. is

Options

A. 48 J
B. 96 J
C. Zero
D. None of these

Answer

D

Explanation

Loss in K.E= (initial K.E- Final K.E) of system
`(1)/(2) m_(1) u_(1)^(2) + (1)/(2) m_(2) u_(2)^(2)- (1)/(2) (m_(1) + m_(2))V^(2)`
`=(1)/(2) 3 xx (32)^(2) + (1)/(2) xx 4 xx (5)^(2)- (1)/(2) xx (3 +4) xx(5)^(2)`
= 986.5J