An 0.0005 kg feather is dropped in the air n floats to the ground at a constant velocity of 2.0m/s?

Question

what is the magnitude of the air resistance (force) acting on the feather ? How long does it take the feather to drop 10.0m?

Answer 1

If the feather floats at a constant velocity of 2.0m/s, it means that it is in equilibrium, i.e. its weight must be equal to the air resistance. Therefore,

Weight=0.0005*9.8
=0.0049N
Air resistance=0.0049N

Again since the feather is floating at a constant velocity of 2m/s, you can use the formula:

Time=Distance/velocity
=10/2
=5s

Note: this formula is not applicable if the feather were accelerating downwards.

Answer 2

Write out what you have been given, then look at the formulas you've been working with (hint: How long does it take for an object moving at 2.0 meters "per second" to go 10.0 meters?)

the air resistance has an equivalent velocity (per second) that the accelleration due to gravity has every second on the feather. Using the formula F=0.5mv^2 where m= mass of feather, and v is the velocity equivalent of the air resistance, can you figure it out?