Suggested time-15 minutes.
A graphing calculator is required for this question.
| t (hours) | 0 | 2 | 5 | 8 | 10 | 12 |
| R(t) (gallons per hour) | 0 | 150 | 300 | 200 | 150 | 50 |
Water flows into a reservoir at a rate modeled by the differentiable function R, where R(t) is measured in gallons per hour and t is measured in hours since pumping began. Values of R(t) for selected values of t, 0 ≤ t≤ 12, are given in the table above.
(a) Using correct units, interpret the meaning of ∫210 R(t) dtin the context of this problem. Use a right Riemann sum with the three subintervals [2, 5], [5, 8], and [8, 10] to approximate the value of ∫210 R(t) dt.
(b) Must there exist a value of c, for 2 < c < 10, such that R′(c) = 0 ? Justify your answer.
(c) Water flows out of the reservoir at a rate modeled by W(t) = 5t e−0.1t, where W(t) is measured in gallons per hour for 0 ≤ t≤ 12. Find the average rate of outflow of water from the reservoir over the time interval 0 ≤ t≤ 12. Show the setup for your calculations.
(d) Find the value of W′(8). Using correct units, interpret the meaning of W′(8) in the context of this problem.
Show the setup of every integral or derivative before evaluating; give decimal answers correct to three places.
Suggested time-15 minutes.
A graphing calculator is required for this question.
A particle moves along the x-axis for 0 ≤ t ≤ 8 seconds. The velocity of the particle is given by v(t) = sin(πt/4) + cos(πt/4), where t is measured in seconds and v(t) is measured in meters per second. At time t = 0, the position of the particle is x(0) = 5 meters.
(a) Find all times t in the open interval 0 < t< 8 at which the particle changes direction. Give a reason for your answer.
(b) Find the acceleration of the particle at time t = 2 seconds. Show the setup for your calculations, and indicate units of measure. Is the particle speeding up or slowing down at time t = 2? Give a reason for your answer.
(c) Find the displacement of the particle over the time interval 0 ≤ t≤ 5. Show the setup for your calculations.
(d) Find the total distance traveled by the particle over the time interval 0 ≤ t≤ 6. Show the setup for your calculations.
Show the setup of every integral or derivative before evaluating; include units where required.