Is the Work-Energy Principle Valid Without Friction?

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evan b
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Homework Statement





Select T-True, F-False, for each statement. If the first is T and the rest F, enter TFFFFF.

A) The work done to raise a box onto a platform depends on how much time it takes to raise it. (Neglect friction, assume it starts on the ground at rest, and ends up resting on the platform)
B) The work done by a constant force acting on an object depends on the orientation of the force relative to the motion of the object
C) Work can be done in the absence of motion.
D) The kinetic energy of an object depends on the direction of the motion involved.
E) The kinetic energy can never be negative.
F) The work-energy principle is not valid if there are frictional forces acting.
 
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evan b said:

Homework Statement



Select T-True, F-False, for each statement. If the first is T and the rest F, enter TFFFFF.

A) The work done to raise a box onto a platform depends on how much time it takes to raise it. (Neglect friction, assume it starts on the ground at rest, and ends up resting on the platform)
B) The work done by a constant force acting on an object depends on the orientation of the force relative to the motion of the object
C) Work can be done in the absence of motion.
D) The kinetic energy of an object depends on the direction of the motion involved.
E) The kinetic energy can never be negative.
F) The work-energy principle is not valid if there are frictional forces acting.

One thing that is definitely true here is that you have to show some effort if you want some help.

So with that in mind, what are your thoughts on the statements?
 
i finaly figured it out. it was FTFFTF.