1. Van
K.E.= 3000 kg (9.8 m/s)^2
= 3000 kg (96.04 m^2/s^2)
= 288,120 kg (m^2/s^2)/2
=144,060 J or kg m^2/s^2
Car
K.E. = 1500 kg (9.8 m/s)^2
= 1500 kg (96.04 m^2/s^2)
= 144,060/2
= 72,030 J or kg m^2/s^2
DIFFERENCE
=144,060 J - 72,030 J
= 72,030
2. K.E. = 3.5 kg (8 m/s)^2
= 3.5 kg (64 m^2/s^2)
= 225/2
= 112 J or kg m^2/s^2