(i)[3]
Find the largest acceleration reached by the car during the first five seconds of its motion.
(ii)[3]
Find how far the car is from its starting point when $t = 5$.
(iii)[5]
The car is at rest when $t = k$. Find the value of $k$.
Mathematics 9709 · AS & A Level · Kinematics of motion in a straight line
Kinematics of motion in a straight line — practice question
A racing car travels along a straight path. Its acceleration $a\,\text{m s}^{-2}$ at time $t\,\text{s}$ after it leaves rest is given by $a = 15t - 3t^2$ for $0 \le t \le 5$, and by $a = \dfrac{625}{t^2}$ for $5 < t \le k$, where $k$ is a constant.
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