a car is moving with speed 30m/s .Due to application of brakes it travels 30m befor stopping .Find its accelaration

Answer 1

average speed during stop = 15 m/s
time to stop = 30/15 = 2 seconds
a =change in speed/change in time= -30/2=-15 m/s^2

Answer 2

speed cannot be taken by equations
By average speed 30+0 /2 = 15 m/s
time taken= dis/speed = 30/15=2 seconds
deaccleration = change in speed / time = -30/2 = -15m/s^2

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