How much work is done by this pushing force? Physics

Question

An person is pushing hefty a carton of mass 33.3 kg at a point of 28 degrees from he flat at a steady speed. The plentifulness of pushing power approaches 222 N. The understudy moves this carton a good ways off of 12.3 meters.

a) How much work is done by this pushing force in overcoming friction?

b) The person gets the box vertically and places it on a rack 1.33 meters high. How much work did the person do?

c)If the person finished lifting the box in 2.55 seconds what was the power of the lift?

Please help me with this problem

Answer 1

Work (W) = Force (F) times distance (d) but ONLY the portion of the force that is applied in the same direction as the movement is counted. In other words, if you push an object straight down (and it didn't move) until you face turns blue, you will have down no work (from the perspective of the physics definition of work).

In your case. you need to use trig to find the portion of the applied force that is in the "x-direction" (the direction of the movement).

F_x = 222cos(28°) = 196 N

W = (196)(12.3) = 2410 Nm or 2410 joules

In the case of lifting the box, the force is its weight (W = mg) or (33.3)(9.91) = 326.7N and lifting it 1.33 meters requires (326.7)(1.33) = 434 Nm or 434 joules

The power is the work divided by the time so 434/2.55 = 170. Watts