We all know that matters are basically of three types: a)solid b)liquid c)gas.
My teacher told me only fluids(liquid and gas)have terminal velocity. Is he correct? I mean if a small ball of iron is falling through a certain type of liquid, will it have a terminal velocity?
In a nutshell do solid objects have terminal velocity?
Terminal velocity is the maximum velocity attained by a body which is falling through a medium when the force of resistance of the medium is equal in magnitude and opposite in direction to the force of gravity.
It is a term popularized by skydivers. When solid objects move through a medium like air or fluid, they experience two types of forces. The driving forces and the resistive forces. For a falling object the driving force would be gravity and for an aeroplane it would be the engine. Solid objects moving through air experience ‘air drag’ while those moving through fluids experience ‘viscous drag’. These are the resistive forces and give rise to fluid friction.At the terminal velocity the driving forces are cancelled out by the resistive forces.
The answers to your questions are :
1.Your teacher was trying to explain that it is the solid object which has terminal velocity and it is caused by the fluid through which it is moving.
2.Yes,the small ball of iron which is falling through a certain type of liquid will .have a terminal velocity.
3. Yes solid objects have terminal velocity when they move through a medium.
Bonus :Also remember that
1. Terminal velocity is possible only when dealing with fluid friction and
2. Fluid friction is different from contact friction like static or kinetic friction.
3. At terminal velocity acceleration of the body is zero.