How Does Air Resistance Affect Work Done on a Falling Raindrop?

[the_d]

A 3.51 x 10^5 kg raindrop falls vertically at
constant speed under the influence of gravity
and air resistance.
The acceleration of gravity is 9.8 m/s^2 :
After the drop has fallen 115 m, what is the
work done by air resistance?

would it be opposite of that done by gravity which i found to be 3.955 x 10^-2?

 

[xanthym]

A 3.51 x 10^5 kg raindrop falls vertically at
constant speed under the influence of gravity
and air resistance.
The acceleration of gravity is 9.8 m/s^2 :
After the drop has fallen 115 m, what is the
work done by air resistance?

would it be opposite of that done by gravity which i found to be 3.955 x 10^-2?

CORRECT.


~~~

 

[dextercioby]

Yes,"constant speed" means that the 2 forces are perfectly balanced.Since they act on the same distance,u could say the the workd done by gravity is equal in modulus with the one done by friction force.

Daniel.

 

[HallsofIvy]

Exactly.

Since the raindrop is falling at constant speed, the net force on it is 0. That means that the air resistance force is equal to but opposite the force of gravity. The work done is just that force times the 115 m distance.