# The motorist

A motorist travelling at $$13 \text{ ms}^{-1}$$ approaches a traffic light which turns red when he is $$25\text m$$ away from the stop line. His reaction time (i.e. the interval between seeing the red line and applying the brakes) is $$0.7\text s$$ and the condition of the road and his tyres are such that the car cannot slow down at a rate of more than $$4.5 \text{ ms}^{-2}$$. If he brakes fully, how far from the stop line will he stop, and on which side of it?

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