A box of mass 4.0 kg hangs by a cable from the ceiling of an elevator. The elevator is moving up at a steady speed of 5.0 m/s for 8.0 m. Use g = 10 m/s2. Match the answers with questions.                                                                          the work done on the box by its weight (WW)                                                                        the work done on the box by the tension force in the cable  (WT)                                                                        the net work done on the box  (Wnet) A. -320 J B. -50 J C. 50 J D. 0 J E. 320 J

A 19.1-kg box is being pushed from the bottom to the top of a frictionless ramp. When the box is pushed at a constant velocity, the nonconservative pushing force does 58.0 J of work. How much work is done by the pushing force when the box starts from rest at the bottom and reaches the top of the same ramp with a speed of 1.50 m/s? Wnc = Number i Save for Later Units Attempts: 0 of 1 used Submit Answer

A 15.1-kg box is being pushed from the bottom to the top of a frictionless ramp. When the box is pushed at a constant velocity, the nonconservative pushing force does 58.0 J of work. How much work is done by the pushing force when the box starts from rest at the bottom and reaches the top of the same ramp with a speed of 1.50 m/s? Wnc = Number i Units

A box slides down a plank of length d that makes an angle of θ with the horizontal as shown. μk is the kinetic coefficient of friction and μs is the static coefficient of friction. 1.Enter an expression for the minimum angle θ (in degrees) the box will begin to slide. 2.Enter an expression for the nonconservative work done by kinetic friction as the block slides down the plank. Assume the box starts from rest and θ is large enough that it will move down the plank.  3.For a plank of any length, at what angle θ (in degrees) will the final speed of the box at the bottom of the plank be 0.85 times the final speed of the box when there is no friction present? Assume μk = 0.39.