Find the speed at which Superman (mass=76.0 kg) must fly into a train (mass = 19969 kg) traveling at 65.0 km/hr to stop it.

1 answer:

4 0

A, speed = 70 km/h x (17026/79) =15086 km/h b, v=u +at v=0, a=-0.5 g = -4.9 m/s^2 u=19.4 m/s t = 3.96 s c, v^2 = u^2 + 2 as as above, 19.4^2 = 2 *0.5 *g *s s = 19.4^2/9.8 = 38.6m

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