A 4.6 kg body is at rest on a frictionless horizontal air track when a constant horizontal force F acting in the positive direction of an x axis along the track is applied to the body. A stroboscopic graph of the position of the body as it slides to the right is shown in the figure. The force F is applied to the body at t = 0, and the graph records the position of the body at 0.50 s intervals. How much work is done on the body by the applied force F between t = 0 and t = 1.8 s? 0.5 s 1.0s 1.5s 2.0 s- 0.2 0.4 0.6 0.8 x (m) Number 0.8 Units

A nonconstant force is exerted on a particle as it moves in the positive direction along the x axis. The figure below shows a graph of this force F, versus the particle's position x. Find the work done by this force on the particle as the particle moves as follows. Fx (N) 12.0 X (m) 4.0 8.0 12.0 16.0 -12.0 (a) From x; = 0 to x = 8.0 m 44 Your response is within 10% of the correct value. This may be due to roundoff error, or you could have a mistake in your calculation. Carry out all intermediate results to at least four-digit accuracy to minimize roundoff error. J (b) From X; = 8.0 to Xf = = 16.0 m |-60 Your response differs from the correct answer by more than 100%. J (c) From x; = 0 to x = 16.0m |-30 The response you submitted has the wrong sign. J

A factory worker moves a 23.0 kgkg crate a distance of 4.50 mm along a level floor at constant velocity by pushing horizontally on it. The coefficient of kinetic friction between the crate and the floor is 0.300.   What magnitude of force must the worker apply?   How much work is done on the crate by the worker's push?   How much work is done on the crate by friction?   How much work is done by the normal force and by the gravity?   What is the net work done on the crate?

A 5.0 kg block moves in a straight line on a horizontal frictionless surface under the influence of a force that varies with position as shown in the figure. The scale of the figure's vertical axis is set by F = 6.00 N. How much work is done by the force as the block moves from the origin to x = 8.0 m? %3D F, 2 4 6 8 Position (m) Number i Units Force (N)