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 – SS, VV, and WW – show measurements taken during the trip, all plotted on the same set of axes with time tt (seconds) on the horizontal axis. Curve S • S(0)=0S(0)=0 and SS is increasing for 0≤t≤100\le t\le 10. • SS has a horizontal tangent at t=0t=0 and the magnitude of its slope increases until t=5t=5, after which the slope decreases. • The graph of SS is concave down on (0,5)(0,5) and concave up on (5,10)(5,10). Curve V • V(0)=0.8 m/sV(0)=0.8\,\text{m/s}. • VV decreases on (0,5)(0,5), reaching V(5)=0V(5)=0, then increases on (5,10)(5,10) to V(10)=0.8 m/sV(10)=0.8\,\text{m/s}. Curve W • W(t)<0W(t)<0 for 0<t<50<t<5 and W(t)>0W(t)>0 for 5<t<105<t<10. • WW is increasing for all tt in (0,10)(0,10). Answer the following. (1) Part 1: (a) Assign each curve – SS, VV, and WW – 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<100<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=5t=5 seconds, citing at least two features visible in the described graphs.

Related theory

Browse the problem library