Which has more kinetic energy: a 0.0010-kg bullet traveling at 394 m/s or a 7.3 107-kg ocean liner traveling at 12 m/s (23 knots)?

Ek-bullet = ?J

Ek ocean liner = ?J

NataleeLeblanc
Feb 19, 2017

#1**+5 **

Seriously? What do you think would happen if you shot the liner head on with your little bullet?.....would it be pushed backwards or stopped?

KE = 1/2 m v^2 Bullet = 77.61 j Liner = 5263704 j

ElectricPavlov
Feb 19, 2017

#2**0 **

EP: You were too generous with the questioner in calculating the KE as:5,263,704 j. You took the mass of the Ocean Liner as 73,107 Kg, or ~73 tonnes. An Ocean Liner can in fact have a mass of between 50,000 - 100,000 metric tonnes. The questioner means: 7.3 x 10^7 Kg=73,000 metric tonnes!!. Therefore, the KE of the Ship would be:5,256,000,000 J.

Guest Feb 19, 2017

#3**0 **

TRUE! I just used 73107 kg......due to poor syntax in question..... it was still ridiculous... yah?

ElectricPavlov
Feb 19, 2017