Question

Calculate the normal force, N, acting on a rider in an elevator if his mass is m=72.1 kg and the acceleration due to gravity g= 9.8m/s^2. The elevator has constant velocity. a) 0 N

b) 406 N
c) 707 N
d) 1008 N

Answer 1

Normal force,
`F_(N)` = 707 N

Given:

Mass of the rider, M = 72.1 kg

acceleration due ti gravity, g = 9.8 m/
`s^(2)`

Velocity of the elevator is constant

Solution:

Since, the elevator is moving with a constant velocity, therefore, the frame we are dealing with is an inertial frame and will not allow any pseudo force to act on it.

The Normal force, N will now be equal to the weight, W of the body which is the product of its mass and the acceleration acting on the body due to gravity and is given by:

`F_(N)` = W =
`M* g`

putting the values in the above formula

`F_(N)` =
`72.1* 9.8 = 706.58 N`

`F_(N)` = 707 N (approx)