Answer to Question #81358 in Physics for Shourya

Question

Three boxes of masses 8kg,2kg and 5kg are placed in the lift one above the another with 8kg at the bottom and 2kg and 5kg above it.when acceleration of the lift is 4m/s^2 then net force on 8 kg box is

Answer 1

If the lift is accelerating upward, then there has to be a “net” or total force acting on the elevator that points upward. Because the box is accelerating with the lift, the same net force acts on the box.
The net or total force is made up of individual forces, which you can identify based on the objects in contact with the box.
Newton's second law of motion can be formally stated as follows:
The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
Thus:
F_net=ma=(8 kg)(4 m/s^2)=32 N