Jawabanmu

2014-01-10T19:48:06+07:00
M=1,8kwintal=1,8.100=180kg
v=72km/jam= 7200/3600 = 2 m/s
Ek= 1/2.m.v^2
    = 1/2.180.2^2
    = 90.4 = 360 J

2014-01-10T20:27:23+07:00
Dik:
m = 1,8 x 100 = 180 kg
v = 72 km/jam = 72000/3600 = 20 m/s
Dit: Ek....?
Peny:
Ek = 1/2 m.v^2
= 1/2 . 180 . 20^2
= 90 . 400
= 36000 kg.m^2/s^2