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# Force - Basic Physics - Need a Better Understanding

Mon 17 Mar, 2014 04:33 pm
I was thinking about a force and the classic equation F=MA. If there is no acceleration does that mean there is no force. So as a practical example, If I am holding a lead weight motionless above the ground, does that mean I am exerting Zero Force? That does not seem right.
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raprap

1
Mon 17 Mar, 2014 05:40 pm
@mattstoc,
You are exerting a force. You are exerting a force that holds the object motionless against the acceleration of gravity. If you were to release that force, the object would freely fall.

Einstein considered acceleration due to motion, and the acceleration of gravity as equivalent, because a physicist standing in a windowless, sealed room could not determine if the room was being accelerated of the room was on the surface of a planet.

Rap
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maxdancona

1
Mon 17 Mar, 2014 06:03 pm
@mattstoc,
If you are holding a lead weight motionless, that means that there is no NET force. You are putting a force upwards. Gravity is putting the same force downwards. You add the two together and you get zero force (and zero acceleration).
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Brandon9000

1
Sat 12 Apr, 2014 09:10 am
Max is exactly correct.
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