Suppose a gangster sprays Superman's chest with 3 g bullets at the rate of 100 bullets/min, and the speed of each bullet is 500 m/s. Suppose too that the bullets rebound straight back with no change in speed. What is the magnitude of the average force on Superman's chest?
this is the question and the answer is apparently 5N. How do we get that? I know that average force is equal to the change in momentum by the change in time. From my calculation I got that 5g hits his chest in a second. So my momentum change should be (5 X 500) - (5 X - 500) from which I am getting 5000N, not 5 N. Help please!
this is the question and the answer is apparently 5N. How do we get that? I know that average force is equal to the change in momentum by the change in time. From my calculation I got that 5g hits his chest in a second. So my momentum change should be (5 X 500) - (5 X - 500) from which I am getting 5000N, not 5 N. Help please!
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I =F*T
P = change in impulse
P=M*V
3 grams becomes 3/1000 =0.003 kg
no change in speed means momentum = impulse because the mass doesn't change so if velocity stays the same there is no change in momentum therefore momentum = impulse btw p means momentum
P=MV
P =0.003*500
P =1.5 kg m/s
I =FT
1.5 =
100 bullets per second becomes 100 *0.003 =0.3 kilograms grams per second (it doesn't work unless it means seconds)
1.5 = F*0.3
F = 5 newtons hope this helps
P = change in impulse
P=M*V
3 grams becomes 3/1000 =0.003 kg
no change in speed means momentum = impulse because the mass doesn't change so if velocity stays the same there is no change in momentum therefore momentum = impulse btw p means momentum
P=MV
P =0.003*500
P =1.5 kg m/s
I =FT
1.5 =
100 bullets per second becomes 100 *0.003 =0.3 kilograms grams per second (it doesn't work unless it means seconds)
1.5 = F*0.3
F = 5 newtons hope this helps
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You underestimate the power of the Force.