Question 1.11: A car moves between two sets of traffic lights, stopping at ...

An Introduction to Mathematics for Engineers: Mechanics

A car moves between two sets of traffic lights, stopping at both. Its speed v $ms^{-1}$ at time t s is modelled by

$v = \frac{1}{20} t (40 – t)$ , 0 ≤ t ≤ 40 .

Find the times at which the car is stationary and the distance between the two sets of traffic lights.

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