Calculating Time, Distance, and Velocity in a Kinematic Problem

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The discussion revolves around a kinematic problem involving a policeman on a motorcycle who accelerates to catch up to a speeding truck. Key points include the need to convert the truck's speed from km/h to m/s and the clarification that the policeman's initial velocity is zero while his acceleration is 1.83 m/s². Participants emphasize that the final velocities of the motorcycle and truck are not necessarily the same when the motorcycle overtakes the truck. The focus is on determining the time and distance traveled by the motorcycle until it matches the truck's position. Understanding the relationship between distance, time, and acceleration is crucial for solving this type of kinematic problem.
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hard kinematic problem, need...help...pls:)

Homework Statement


A policeman (on a motorcycle, with the engine going) is hiding behind a bush on the side of the road when a speeding truck passes with a speed of 96.5 km/h. As the truck passess he sets off with an acceleration of 1.83 m/s, which he maintains until he overtakes it. Calculate:
a) the time he took to overtake the truck
b) the distance he traveled in doing so
c) the velocity, in km/h, of the motor cycle when it catches the truck.


Homework Equations




The Attempt at a Solution



Well first i converted 96.5 hm/h into m/s which is 26.8 m/s and i know that his acceleration doesn't change, I am just wondering is the policeman's final velocity the speed that the truck is traveling at which is 26.8 m/s? And is his initial velocity 0? and his acceleration is 1.83 so i thort that i cud use v=u+at to work out a)
i think I am on the wrong track though actually I pretty sure I am. Can someone pls help me and also can sum1 pls tell me sum things that i shud look out for when trying to solve these really hard straight line motion questions. Like i get the simple ones but it is just ones similar to these that i find difficult. I appreciate all the help! Thankyou!:)
 
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9giddjl said:
im just wondering is the policeman's final velocity the speed that the truck is traveling at which is 26.8 m/s?
You can't assume that the final two velocities are the same, in some cases it may very well be that the two have the same final velocity, but this is not generally the case.

Instead, what do you know about the distance between the truck and the bike at the time your trying to find?
 
um i don't know a distance.. or maybe I cannot see it
 
9giddjl said:
um i don't know a distance.. or maybe I cannot see it
When the bike is level with the truck, where is their separation?
 
they're at the same distance?
 
so we need to find the time when the distances are the same?
 
9giddjl said:
they're at the same distance?
9giddjl said:
so we need to find the time when the distances are the same?
Correct :approve:
 

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