A cart of mass is first pulled along a horizontal road by a constant force of for a…
PHYSICS · Subjective · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A cart of mass 40kg is first pulled along a horizontal road by a constant force of 90N for a distance of 50m. Immediately afterwards it is pulled up a rough incline 8m long that rises 3m vertically. The same 90N pulling force acts parallel to the path on the incline, while a frictional force of 30N opposes the motion there. The entire journey takes 40s. Take g=9.8m/s2.
(i) Calculate the work done by the pulling force on the horizontal road segment.
(ii) Calculate the work done against gravity while the cart moves up the incline.
(iii) Calculate the work done against friction on the incline.
(iv) Find the total work done on the cart for the whole journey.
(v) Determine the average power developed during the 40s trip.