- #1
JZC
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I was having a discussion with a friend and neither of us could come to a conclusion.
The question is, what is the force acting on an object, by the ground, if it is released from a heigh?
This is how we related it:
If the object is on the floor, there is a weight and normal force acting on it, and since it isn't accelerating, Weight is equal to normal force by Newtons second law.
If it falls for a distance:
I am sort of stuck with a FBD and KD. When the object is free falling, ma = mg. However, if I draw a FBD and KD at the instant it is at impact, I get a net force of 0.
positive in the up direction
Normal Force - Weight = -ma
normal force = weight - ma
________
this would show that the normal force applied on the object is less than if the object was at rest. It does not make sense to me.
My friend suggested that the force will be the same for both, but I am reluctant about that.
The question is, what is the force acting on an object, by the ground, if it is released from a heigh?
This is how we related it:
If the object is on the floor, there is a weight and normal force acting on it, and since it isn't accelerating, Weight is equal to normal force by Newtons second law.
If it falls for a distance:
I am sort of stuck with a FBD and KD. When the object is free falling, ma = mg. However, if I draw a FBD and KD at the instant it is at impact, I get a net force of 0.
positive in the up direction
Normal Force - Weight = -ma
normal force = weight - ma
________
this would show that the normal force applied on the object is less than if the object was at rest. It does not make sense to me.
My friend suggested that the force will be the same for both, but I am reluctant about that.