Cogito
AP Calculus AB · Chapter 4 · Lesson 1
Motion and Related Rates
Derivatives with units attached.
11 problems · about 25 minutes · AP Calculus AB 4.1, 4.4, 4.5
Figure — use these to answer the problems
- Point(1, -3)
- Slope of the tangent-1
Warm Up
Straightforward practice. Get the method working first.
4 problemsVelocity −4, acceleration 6. Speeding up? 1 for yes, 0 for no.
AnswerVelocity 5, acceleration 2. Speeding up? 1 for yes, 0 for no.
AnswerVelocity 5, acceleration −2. Speeding up? 1 for yes, 0 for no.
AnswerVelocity −6, acceleration −3. Speeding up? 1 for yes, 0 for no.
Answer
Build It Up
The same ideas with more to keep track of.
3 problemsOrder the steps of a related-rates problem.
Write 1 to 4 in the boxes to put these in order.
- Write a relationship between the quantities
- Differentiate both sides with respect to time
- Substitute the known values and rates
- Solve for the unknown rate
Position s(t) = t². What is the velocity at t = 3?
AnswerSame position function. What is the acceleration?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsVelocity −3. Is the object moving forwards? 1 for yes, 0 for no.
AnswerSpeed is 9 and the object moves backwards. What is the velocity?
AnswerSpeed
Velocity is −7. What is the speed?
AnswerAt Rest
An object is momentarily at rest. What is its velocity?
Answer