Q16 of 25 Page 130

In which case the magnitude of acceleration will be greater when a car starts from rest or when the brakes are applied suddenly?

When a car starts moving it begins to gain velocity, that is, the acceleration is positive because acceleration is the rate of change of velocity. When brakes are applied the moving car loses its velocity, and further may come to rest. So, here the acceleration is negative.

Hence, acceleration in case of the car starting from rest is greater as it is positive, more than the acceleration of a car applying brake where it is negative.


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