1. Pumping out a Tank
How rapidly will the fluid level inside a vertical cylindrical tank drop if we pump the fluid out at the rate of 3000 L/min?

2. Cont’d r h
Fluid Volume:
V = πr2h

3. Cont’d
As time passes, the radius remains constant but V and h change. We think of V and h as differentiable function of time and use t to represent time. We have

4. A rising Balloon
A hot-air balloon rising straight up from a level field is tracked by a range finder 500 ft from the point of lift-off. At the moment the range finder’s elevation angle is π/4 degree, the angle is increasing at the rate
of 0.14 rad/min. How fast is the balloon rising at that moment?

5. A rising Balloon

6. Cont’d