Work and net work question - Thanks

[nukeman]

Homework Statement

Here is the question:

"A ball moves through the air, and experiences a force of air resistance, in addition to the force of gravity. While it moves, its total mechanical energy decreases by 15J, and its gravitational potential evergy decreases by 25J"

A: What is the net work done on this ball by all the forces acting on it?

B: What is the work done on the ball by the force of air resistance.

C: What is the work done on the ball by the force of Gravity?

Homework Equations

The Attempt at a Solution

I'm not sure which formulas to use here... Can anyone help me out?

 

[berkeman]

Homework Statement

Here is the question:

"A ball moves through the air, and experiences a force of air resistance, in addition to the force of gravity. While it moves, its total mechanical energy decreases by 15J, and its gravitational potential evergy decreases by 25J"

A: What is the net work done on this ball by all the forces acting on it?

B: What is the work done on the ball by the force of air resistance.

C: What is the work done on the ball by the force of Gravity?

Homework Equations

The Attempt at a Solution

I'm not sure which formulas to use here... Can anyone help me out?

What are the units of work? If a mass' vertical position is changed, what happens to its gravitational potential energy? What is the equation for gravitational PE in terms of the mass and the change in height?

What is the question referring to when it uses the term "mechanical energy"? What is the more common/scientific term for this?