Question

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1. doubling your speed multiplies your stopping distance by:

stopping distance remains constant
twice as much
three times as much
four times as much

1. a flashing red light at a traffic signal means:

you may proceed with caution
you must come to a complete stop
the light is about to change

Explanation:

Question 1

Stopping distance is related to the square of speed (from kinematic equations, \(d \propto v^2\) where \(d\) is stopping distance and \(v\) is speed). If speed doubles (\(v_2 = 2v_1\)), then \(d_2 \propto (2v_1)^2=4v_1^2\), so \(d_2 = 4d_1\). Thus doubling speed multiplies stopping distance by four.

A flashing red traffic light is equivalent to a stop sign, meaning drivers must come to a complete stop before proceeding when safe. "Proceed with caution" is for flashing yellow, and "light about to change" is for amber (yellow) or flashing yellow in some contexts, not red.

Answer:

Four times as much

Question 2