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Physics
Forces, energy, circuits, and the sign conventions that trip everyone up.
Kinematics
what is the difference between velocity and speed
why is acceleration still negative at the top of a throw
how do you choose a sign convention in kinematics
Forces
why do you draw a free body diagram
what is the difference between mass and weight
why is the normal force not always equal to weight
Circuits
why does current stay the same in a series circuit
what is the difference between series and parallel circuits
Momentum
what is the difference between elastic and inelastic collisions
when is momentum conserved but kinetic energy is not
Circular motion
is centrifugal force real
why does centripetal force point inward
Work and energy
why is the work zero when you carry something at constant height
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