A car is traveling 20 m/s when the driver sees a child standing in the road. He steps on the brakes and slows down at 7.0 m/s^2. His reaction takes 0.9 seconds. What is the final velocity of this car?
whats the example leading to the answer please! and thank you
whats the example leading to the answer please! and thank you
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velocity, u = 20 m/s
acceleration, a = -7 m/s^2
time = 0.9 sec
final velocity, v = 20 +(-7)(0.9),
v = 20 - 6.3 = 13.7 m/s >===============< ANSWER
acceleration, a = -7 m/s^2
time = 0.9 sec
final velocity, v = 20 +(-7)(0.9),
v = 20 - 6.3 = 13.7 m/s >===============< ANSWER
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use should use the formula v=u+at
v=(20)+(-7.0)(0.9)
v=13.7m/s^-1
v=(20)+(-7.0)(0.9)
v=13.7m/s^-1