Question #e1ca3

1 Answer
Feb 22, 2017

You got it correct.

Explanation:

Let the speed of 2kg ball be #=v# #ms^-1#
1kg ball has speed #=2v# #ms^-1#
Kinetic energy is given as #=1/2mv^2# ......(1)

Using equation (1) we get
#KE_"2kg"=1/2 (2)v^2=v^2# .....(2)
and #KE_"1kg"=1/2(1)(2v)^2=2v^2# ......(3)

Dividing (2) with (3)
#(KE_"2kg")/(KE_"1kg")=v^2/(2v^2)#
#=>(KE_"2kg")/(KE_"1kg")=1/(2)#

#=># Compared to the 1kg ball, the 2kg ball has half the kinetic energy.