Question

Q]. A bike is moving with a velocity of 80m/s towards east .He suddenly applies brake such tha a retardation of 2m/s²is produced . Calculate how much time Bike will take to come into rest​

Answer 1

Answer:

Given :-

• Initial velocity = 80 m/s

• Final velocity = 0 m/s

• Acceleration = -2 m/s²

Hints :-

• Final velocity cames as zero because brakes are applied to a moving cycle.

• Acceleration cames in negative because breaks are applied and the cycle retards. And also we know that when the final velocity is less than initial velocity then retardation happens.

Find Out :-

The time taken by the cyclist to come to rest.

Solution:

First equation of motion

Using formula:

$\red{ \boxed{\sf{v =\: u + at}}}$

➙ 0 = 80 + (- 2)t

➙ 0 = 80 - 2t

➙ 0 - 80 = - 2t

➙ - 80 = - 2t

➙ 80 = 2t

➙ $\sf \dfrac{80}{2} =\: t$

➙ ${\small{\bold{\purple{\underline{t =\: 40\: seconds}}}}}$

Henceforth, the time bike will take to come into rest is 40 seconds.