Question

A solid sphere falls with a terminal velocity of 20 m s^-1 in air. If it is allowed to fall in vacuum, the terminal velocity will be .

• A. ^{$20{\mathrm{ms}}^{-1}$}
• B. ^{$0{\mathrm{ms}}^{-1}$}
• C. ^{$10{\mathrm{ms}}^{-1}$}
• D. never attained

Answer 1

The correct option is D never attained

As there is a viscous force acting on the object (due to friction), because of the presence of surrounding medium, it attains a uniform velocity after sometime.

But if there is no medium to resist the motion of the object, it will continuously increase its velocity and terminal velocity will never be attained.