The BRAKING time to stop is
T = 25/3.75 = 6.667 s
The distance travelled while decelerating is:
Vaverage*T = (1/2)(25)*6.667 = 83.33 m
She can travel only 95-83.3 = 11.7 m before applying the brakes.
Her reaction time must be t = 11.7/25.0 = 0.47 seconds or less, since 11.7 m is the maximum distance she can travel, at 25 m/s, before braking.
A vehicle is travelling at 25.0 m/s. It brakes provide an acceleration of -3.75 m/s^2[forward]. What is the driver's maximum reaction time if she is to avoid hitting an obstacle 95.0 m away?
the answer is a number less than 0.5 second. can you tell me the exact number and can you show me how to solve it?
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physics is hard
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