19. Incorrect In a combustion engine, gas is burned. The resulting explosion produces a force that drives the pistons in the engine. The force of the explosion on the piston is due to the change in momentum of the gas molecules. A 0.4-g sample of gas produces a force of 2400 N in an explosion that lasts 10e-3 seconds. What must be the speed of the gas molecules?(adsbygoogle = window.adsbygoogle || []).push({});

My answer: 6 x 10e3 m/s

The correct answer: 3 x 10e3 m/s

I used the impluse force = change in momentum forumla

ft = mv

2400(10e-3) = .0004(x)

and solved to get 6e3 m/s

What am I missing?

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# Homework Help: Cofused with this Momentum problem

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