Why Does a Feather Hit the Ground Later Than a Steel Ball?

[Fullmetalx]

Homework Statement

Suppose you drop a feather and a steel ball of equal masses (0.014 kg) at the same time from a height of 1.5 m and you are told that the feather hits the floor 3.5 s after the steel ball. Estimate the value of the terminal velocity of the feather in air.

Estimate the feather's drag coefficient.

Homework Equations

v=mg/c

The Attempt at a Solution

I assumed the drag on the steel ball is negligible. So i used r=vit +.5at^2 to find the time it takes for it reach the ground. I then added 3.5s and used another kinematic equation to find the final velocity or terminal velocity. I then plugged the answer into the above equation to find c. it was wrong

 

[Simon Bridge]

What does the v-t graph of the feather look like?
i.e. do the kinematic equations even apply to it's motion?

Consider: if the air-resistance for the steel ball can be neglected - so it never reaches it's terminal velocity - then what is the case for the feather? How long does it take the feather to reach it's terminal velocity?

 

[Chestermiller]

Assume that the feather reaches its terminal velocity instantaneously. How far did it fall? How many seconds did it take to fall this distance? What was its velocity?