Contextual Applications unit test
A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.
Displacement
Decreasing at a decreasing rate
Average velocity versus instantaneous
Tangent-line estimate and concavity
Increasing at a decreasing rate
Speed is not a derivative
Common related-rates error
Negative acceleration does not mean slowing
Position from velocity
Displacement vs total distance
Rate versus change versus amount
L'Hôpital's Rule
Short answer 1. Define or explain: L’Hôpital differentiates separately
3 ptsShort answer 2. Define or explain: Related rates procedure
3 ptsShort answer 3. Define or explain: Units as a setup check
3 ptsShort answer 4. Define or explain: Total distance
3 ptsFree response
9 ptsAn inverted right circular cone has a radius of 5 cm at its top and a height of 10 cm. Water drains out of the cone at a constant rate of 8 cubic centimeters per minute. Let h be the depth of the water in centimeters and r the radius of the water surface in centimeters. The volume of a cone is V = (1/3)πr²h.
Use similar triangles to express r in terms of h, and hence write V as a function of h alone.
Find the rate at which the water level is falling at the instant when the depth is 6 cm. Include units.
Find dr/dt at that same instant. Then explain why dh/dt is not constant even though dV/dt is.