Please answer both questions. Thanks!!!! 1.) Select T-True, F-False, for each st
ID: 1600798 • Letter: P
Question
Please answer both questions. Thanks!!!!
1.)
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 fast it is raised. (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 is independent of the orientation of the force relative to the motion of the object
C) The work-energy principle is not valid if there are frictional forces acting.
D) Work can be done in the absence of motion.
E) The kinetic energy can be positive or negative.
F) The kinetic energy of an object is independent of the direction of the motion involved.
2.)
The graph shows the upward speed of a ball thrown up with an initial speed of 27.0 m/s from the surface of Jupiter.
Select whether an answer is True or False (for example, if only B is True, enter FTFFFF).
A) The velocity vector and the acceleration vector are in the same direction after t=1.2s.
B) The acceleration is constant.
C) The ball's KE increases during the first second.
D) Maximum height is reached at about t=1.2s.
E) The acceleration is 0 near t=1.2s.
F) The ball's PE is a constant.
Explanation / Answer
1)
A) F
B) F
C) F
D) F
E) F
F) T
Because, Workdone is the scalar product of force and displacement.
W = F.d = F*d*cos(theta) here theta is the angle between F and d.
2)
A) T
B) T
C) F
D) T
E) F
F) F