It takes 60.0 s to pass A and another 60.0 s to pass from A to B. find the velocities of the car when it passes milestone A and milestone B.
Solutions please and why. Thank you!
Solutions please and why. Thank you!
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Assume constant acceleration a. The distance to A is not given.
We can write:
t = 60s
250m = V1*t + 1/2 *a*t^2 = V1*60 + 1800*a
Where V1 is the Velocity at A
We know that:
V1 = a*t = a*60
Substitute that into the first equation:
250 = (a*60)*60 + 1800*a = [3600+1800]*a = 5400*a => a = 250/5400 = 0.046m/s^2
V1 = 60*a = 2.78m/s <---------------- Velocity at A
V2 = a*2*60 = 5.56m/s<---------------- Velocity at B
We can write:
t = 60s
250m = V1*t + 1/2 *a*t^2 = V1*60 + 1800*a
Where V1 is the Velocity at A
We know that:
V1 = a*t = a*60
Substitute that into the first equation:
250 = (a*60)*60 + 1800*a = [3600+1800]*a = 5400*a => a = 250/5400 = 0.046m/s^2
V1 = 60*a = 2.78m/s <---------------- Velocity at A
V2 = a*2*60 = 5.56m/s<---------------- Velocity at B