Question

A man of mass $90kg$ is standing in an elevator whose cable broke suddenly. If the elevator falls freely, the force exerted by the floor on the man is

• A. $90N$
• B. $180N$
• C. $ZeroN$
• D. Any negative value

Answer 1

The correct option is C $ZeroN$

Given that,

Mass $M=90kg$

Now, If the elevator falls freely

So, the downward acceleration of the man in the elevator is

$a=g$

Now, the force is

The force exerted by the floor on a man = actual weight of man $-$ net upward force on a man

$F=ma-mg$

$F=mg-mg$

$F=0N$

Hence, the force exerted by the floor on a man is zero