Question

a person of mass 70 kg is standing in an elevator that is moving downward. the speed decreases uniformly from 4.0 m/s to zero in 2.0 s. what is the normal force acting on the person?

Answer 1

The normal reaction of the boy of mass 70 kg is 826 N.

Let us understand about normal reaction.

The force exerted by a surface on an object in contact with it which prevents the object from passing through the surface is called Normal reaction.

To calculate the normal reaction, we use the formula below.

Formula:

N = mg+m(v-u)/t.......... Equation 1

Where:

N = Normal reaction

m = Mass of the person

g = Acceleration due to gravity

v = Final Velocity

u = Initial velocity

t = Time

From the question,

Given:

m = 70 kg

v = 4 m/s

u = 0 m/s

t = 2 s

g = 9.8 m/s²

Substitute these values into equation 1

N = (70×9.8)+70(4-0)/2

N = 686+140

N = 826 N

Hence, the normal reaction of the boy is 826 N.

Learn more about normal reaction here: brainly.com/question/28788588

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