Q29 of 35 Page 55

A particle starts with initial speed u and retardation a to come to rest in time T. The time taken to cover first half of the total path travelled is?

Here,

Initial speed = u Final Speed = v


Retardation = a Acceleration = –a


Time taken to come to rest = T


Now, using equations of motion, we get:


..A


..1


Also using another equation of motion:




..2


Now, putting 2 in 1, we get:



..3


Now, for the first half of the path distance covered =


Let the time taken = t


So, using 1 we get:





Now, this is a quadratic equation, on solving this we get:



Since t < T, So,


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