true free fall is possible only in vacuum
Answers
Answer:
A true free fall is possible in case of vacuum. This is because in vacuum, the force of viscosity is not offered by the air (or any other fluid). This makes your acceleration during fall exactly equal to 'g', i.e.; . Thus, you may consider it to be a true free fall....
Answer:
Not necessarily. One can think of a smart contraption that would engender free fall in an atmosphere.
Consider an aerodynamic, bomb-like container falling vertically through the atmosphere assisted by a controlled-thrust motor. The sole purpose of the motor and its control system is to maintain at all times a downward acceleration that equals exactly that of the local free fall.
Now, let the container’s interior be a pressure vessel pressurized with a gas of whatever constitution and let a heavy metal ball be suspended in the center of the vessel without touching the walls. If that’s initially the case, then, on account of the container’s downward acceleration, the ball would keep motionless with respect to the walls and away from them throughout the container’s fall.That ball would be both immersed in an atmosphere and in a state of free fall.