(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A motorbike is riding along a straight road at 25m/s when the rider suddenly notices that there is a broken down car in his way, 65 meters ahead. He immediately brakes giving the bike a constant deceleration of 5m/s^2.

A. How far in front of the car does the biker come to a stop?

B. If the biker had not reacted a soon as he did and applied the brakes 1 second later, what speed would the bike had hit the car?

2. Relevant equations

v=u+at

v^2=u^2+2as

s=1/2(u+v)t

s=ut+1/2at^2

3. The attempt at a solution

The question confuses me a little as the question gives a distance of 65m in the question but asks you to also find a distance. But anyways, my attempts are below...

Part A:

v=0 a=-5 u=25

v^2=u^2+2as

0=625+(2x-5xs)

0=625+(-10xs)

s=(625-0)/-10

s=2.5m

Part B:

v=0 t=1 a=-5 s=65

s=1/2(u+v)t

65=1/2(25+v)1

v=65/12.5

v=5.2m/s

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# Homework Help: Constant Acceleration Problem

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