AP Physics C: Mechanics : Understanding Newton's Laws
Study concepts, example questions & explanations for AP Physics C: Mechanics
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Example Questions
Example Question #1 : Newton's Laws And Force Diagrams
A 
Relevant equations:
Determine the clockwise torque caused by the bucket.
Write an expression for the counterclockwise torque caused by the rope.
Combine the torque of the rope and the torque of the bucket into the net torque equation.
Since the system has no angular acceleration, net torque must be zero, allowing us to solve for the force of the rope.
Example Question #32 : Forces
An object at rest will remain at rest unless acted on by a(n) __________.
internal force
external force
positive force
negative force
external force
The correct answer is external force. External forces applied to an object will result in non-zero acceleration, causing the object to move. In contrast, internal forces contribute to the properties of the object and do not result in acceleration of the object.
Either positive or negative forces can result in the acceleration of an object. The sign on the force simply conveys information about its relative direction.
All AP Physics C: Mechanics Resources
