How Is the Man's Mass Calculated from Throwing a Ball on Ice?

Thread starter davedays
Start date Nov 3, 2009
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Ball Momentum

AI Thread Summary

The problem involves calculating a man's mass based on the momentum conservation principle after he throws a ball on ice. Given the ball's mass of 250 grams and a speed of 8.0 m/s, the man moves backward at 0.05 m/s. Using the equation for momentum (m1 v1 = m2 v2), the calculation shows that the man's mass is 40 kg. The solution is confirmed as correct by another participant in the discussion. This demonstrates the application of physics principles in real-world scenarios.

Nov 3, 2009

davedays

Homework Statement

A man is standing on a frozen pond (which is mean less).
He throws a ball m=250 g
The speed of the ball is 8.0 ms^-1
The man moves back at a speed of 0.05 ms^-1
How heavy is the man ?

Homework Equations

p1=p2
m1 x v1 = m2 x v2

The Attempt at a Solution

p1=p2
m1 v1 = m2 v2

250 x 8 = m2 x 0.05
2000 = 0.05 m2
m2= 40000 [g] = 40 [kg]

is this correct ?

Thanks,
dave

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Nov 3, 2009

Cryphonus

Correct.

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