CALCULUS AB

WORKSHEET ON PARTICLE MOTION & OPTIMIZATION

1. A particle moves along a vertical line so that its position at any time is given by

, where s is measured in meters and t in seconds.

(a) When is the particle moving down? Justify your answers.

(b) Find the displacement of the particle after 5 seconds. Show the work that leads to your answer.

(c) Find the distance traveled by the particle between t = 0 and t = 5 seconds. Show the work

that leads to your answer.

(d) When is the particle slowing down? Justify your answer.

2. A particle’s position at time t seconds, , is given by where t is measured in

seconds and s is measured in meters. Find the acceleration of the particle each time the velocity is

zero.

3. A drilling rig 6 miles offshore is to be connected to a refinery on Rig

shore, 18 miles down the coast from the rig by using underwater

pipe from the rig to point and land-based pipe from point P to the

refinery. If underwater pipe costs $50,000 per mile and land-based 6

pipe costs $35,000 per mile, how far should point P be from the

refinery to minimize the cost? What will the cost be? Give the cost P

to the nearest cent. Use Calculus to find and justify your answer. Refinery

4.

t (sec) / 0 / 4 / 7 / 12 / 15
meters/sec / 5 / 9 / / /

The velocity of a particle moving along the x-axis is modeled by a differentiable function v, where

the position x is measured in meters. and time t is measured in seconds. Selected values of

are given in the table above.

(a) Use data from the table to estimate the acceleration of the particle at t = 6 seconds. Show the

computations that lead to your answer.

(b) Based on the values in the table, what is the smallest number of instances at which the

velocity could equal 0 on the interval 0 < t < 15? Justify your answer.

5. A cylindrical container has a volume of . Find the radius and height of the cylinder so

that its surface area will be a minimum. Use Calculus to find and to justify your answer.

(Volume of a cylinder = . Surface area of a cylinder = .)