1. Tardigrade
  2. Question
  3. Physics
  4. Assertion: Two bodies of masses M and m (M > m) are allowed to fall from the same height if the air resistance for each be the same then both the bodies will reach the earth simultaneously. Reason: For same air resistance, acceleration of both the bodies will be same.

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. Assertion : Two bodies of masses $M$ and $m (M > m)$ are allowed to fall from the same height if the air resistance for each be the same then both the bodies will reach the earth simultaneously.
Reason : For same air resistance, acceleration of both the bodies will be same.

AIIMSAIIMS 2017Laws of Motion

Solution:

The force acting on the body of mass M are its weight Mg acting vertically downwards and air resistance F acting vertically upward.
$\therefore $ Acceleration of the body
$a=\frac{mg-F}{M}=g-\frac{F}{M}$
Now, M > m, therefore, the body with larger mass will have greater acceleration and it will reach the ground first.