A car travels along a straight road for 10 seconds
MATHEMATICS · Multi-part · AP · Calculus AB · Contextual Applications of Differentiation · Contextual Applications of Differentiation
Problem
A car travels along a straight road for 10 seconds. Three smooth curves – S, V, and W – show measurements taken during the trip, all plotted on the same set of axes with time t (seconds) on the horizontal axis.
Curve S
• S(0)=0 and S is increasing for 0≤t≤10.
• S has a horizontal tangent at t=0 and the magnitude of its slope increases until t=5, after which the slope decreases.
• The graph of S is concave down on (0,5) and concave up on (5,10).
Curve V
• V(0)=0.8m/s.
• V decreases on (0,5), reaching V(5)=0, then increases on (5,10) to V(10)=0.8m/s.
Curve W
• W(t)<0 for 0<t<5 and W(t)>0 for 5<t<10.
• W is increasing for all t in (0,10).
Answer the following.
(1) Part 1: (a) Assign each curve – S, V, and W – to one of the following quantities of the car: position, velocity, or acceleration. Clearly state your assignment.
(2) Part 2: (b) For the time interval 0<t<10, determine all subintervals on which the car is speeding up. Justify your answer using relationships among the curves you identified in Part 1.
(3) Part 3: (c) Explain why the car’s speed is minimal at t=5 seconds, citing at least two features visible in the described graphs.