Question

A car (mass of 830 kg) is sitting on a car lift in a shop (neglect the mass of the lift itself). While the car is being lifted up, it is speeding up with 3.8 m/s2. What is the magnitude of the lifting force?

Answer 1

There are two force acting on an object that is being lifted. (1) the weight of the car, (2) the upward force. The difference of these force should be equal to the product of the mass and the acceleration. (This is the content of Newton's 2nd Law of Motion). If we let the lifting force be F,
                       F - (830)(9.8) = (830)(3.8)
The value of F from the equation is 11288 N.