<PRE><B>Question 987987</B>
A car waiting on a signal line starts moving with a uniform acceleration of 4m/s^2 , when traffic lights turn green . at the same time a motor cyclist moving with a constant speed of 36 km/h passes the car.find out 
a)the distance from signal line at which the car driver over takes the motorcyclist and,
b) speed of car at that time.
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36 km/hr = 10 m/sec
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find out 
a)the distance from signal line at which the car driver over takes the motorcyclist
s(t) for the car = at^2/2 = 2t^2 meters
s(t) for the MC = 10t meters
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2t^2 = 10t
t = 0 (at the light)
t = 5 seconds.
s = 50 meters
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b) speed of car at that time.
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v = at = 4*5
v = 20 m/sec</PRE>