Question

Assertion : A man in a closed cabin which is falling freely does not experience gravity.
Reason : Inertial and gravitational mass have equivalence.

• A. If both assertion and reason are true and reason is the correct explanation of the assertion
• B. If both assertion and reason are true but reason is not the correct explanation of the assertion
• C. If assertion is true, but reason is false
• D. Both assertion and reason are false statements

Answer 1

Answer: (A)

In a closed cabin falling freely, the forces are acting on the man as shown:

$mg-R=mg$
or $R=mg-mg$
$=0$
Since, reaction on the man is zero, hence, man does not experience gravity.
Inertial mass of a body is the ratio of net force acting on the body to the acceleation produces in the body, i.e.,
$m=\frac{F}{a}$
Gravitational mass of a body is the ratio of gravitational force acting on the body to the acceleration due to gravity,
$m=\frac{w}{g}$
Inertial mass and gravitational mass are equivalent.