why is a hand rests on a table more to injury if you catch a lead ball than it is in the air at same height?

Answer 1

Because the tide looks up if you are in center feild.

Answer 2

What ? Has the English language been abolished while I've been out or what ? This question makes no sense. What you should ask is 'Why is a hand more likely to suffer injury if a lead ball is dropped on it while it is resting on a table that when simply held in the air at the same height ?'

The answer is that the kinetic energy and weight of the ball has nowhere to be dispersed when the hand is on the table, whereas most of the energy will be dispersed by the hand dropping under the weight of the ball in the second case.

Answer 3

Because the hand cannot move, the lead ball decellerates in a much shorter time. This makes the hand absorb the energy over a much shorter time.
Like jamming on the brakes in a car.

Answer 4

That is easy ..
application of newton's laws of motion.. ( remember,
F =ma {Second Law})
When your is resting on the table and you catch a ball (Of heavy mass as of lead) then you bring the Ball's velocity to zero (i.e. to stop it) in a very very short interval of time.. almost instantly..
Hence the Force which acts on your hand is quite large..
But when we catch a ball otherwise, it is (unconsciously) customary (as you must have observed) that we lower our hand while catching it (which we can not when it is resting on table)
... Hence, the time to bring the ball velocity to zero is increased.... thereby decreasing its acc. gradually which lessens the force it exerts on our hand.. and we are less likely to get hurt..
..
The cushions and shock absorbers work the same way, i.e. by increasing the time to bring a thing to halt.

Simple. isn't it...
Hope that finds use to you..

Answer 5

It's not the fall that hurts it's the sudden stop.