- #1
TheRedDevil18
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I just want to confirm if what I am doing is right, please correct me because my textbook gives me a different answer.
The mass of a minibus with the driver is 1.5*10^3 kg. The driver is moving at a speed of 30m.s when he notices that the traffic lights ahead have turned red. He applies a force of 9*10^3 N on the brake pedal.
A) How far must he have been from the traffic lights if he were able to stop in time?
a=Fnet/m
s=d/t
a=9*10^3/1.5*10^3
= 6 m.s^-2
using the equation a=v/t i got a time of 5 seconds
so
d = s*t
= 30*5
= 150 m but my textbook says it is 75 m
Homework Statement
The mass of a minibus with the driver is 1.5*10^3 kg. The driver is moving at a speed of 30m.s when he notices that the traffic lights ahead have turned red. He applies a force of 9*10^3 N on the brake pedal.
A) How far must he have been from the traffic lights if he were able to stop in time?
Homework Equations
a=Fnet/m
s=d/t
The Attempt at a Solution
a=9*10^3/1.5*10^3
= 6 m.s^-2
using the equation a=v/t i got a time of 5 seconds
so
d = s*t
= 30*5
= 150 m but my textbook says it is 75 m