I've been stuck on this problem and hope someone can help me. A man is standing on scales which show his weight as 607.6 N. A .50 kg ball is dropped from a height of 1 m into his hands. His hands drop 25 cm from chest level to waist level during the catch.His mass is 62 kg. If he decelerates the ball uniformly during the catch what would be the max. reading on the scales? Please, I need help on this one.
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Hi again, Can anyone please help me with the physics problem I posted at 3:47 p.m. today (sunday). I would really, really appreciate it. Thanks!
The ball applies a force to the man as he decelerates it. The ball first touches his hands with a speed of sqrt(2*g*1m) = 4.42 m/s. He decelerates it as it falls X = 0.25 m. The deceleration rate is a = V/[X/(V/2)] = V^2/(2X)= 39.1 m/s^2.
The force applied to the man by the ball (and vice versa) is 0.5*39.1 = 19.5 N. This will show up as extra scale weight as the ball is being decelerated.
There will be an additional effect of the man lowering his center of gravity as he lowers his arms, but without knowing the mass of his arms, I cannot compute it. It could exceed the increased weight effect of catching the ball, and be in the opposite direction. Whoever created this question should be aware of this complication.
The force applied to the man by the ball (and vice versa) is 0.5*39.1 = 19.5 N. This will show up as extra scale weight as the ball is being decelerated.
There will be an additional effect of the man lowering his center of gravity as he lowers his arms, but without knowing the mass of his arms, I cannot compute it. It could exceed the increased weight effect of catching the ball, and be in the opposite direction. Whoever created this question should be aware of this complication.
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