Question

For a physics class experiment, you place a Red Delicious apple of mass m=0.100 kg at rest on a bathroom scale, and place the combination on the floor of an elevator in a tall building as shown in the Figure. The elevator is initially at rest. Suppose the elevator has been summoned by someone on a higher floor. While the elevator is speeding up and traveling upward (in the +y direction), it has an acceleration of ay=1.00 m/s2 . What is the magnitude of the normal force on the apple due to the scale when the elevator is speeding up?

Cable Elevator Apple- Bathroom scale Figure: An apple sits on a bathroom scale that rests on the floor of an elevator. Initially, the elevator is at rest.

Answer 1

Free Body Diagram

Gravitational acceleration = g = 9.8 m/s²

Mass of the apple = m = 0.1 kg

Acceleration of the elevator = a = 1 m/s² upwards

Normal force on the apple = N

From the free body diagram,

ma = N - mg

(0.1)(1) = N - (0.1)(9.8)

N = 1.08 N

Magnitude of the normal force on the apple = 1.08 N