Approaching a Cops and Robbers Chase Problem Using Equations of Motion

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Deep Dhillon
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Homework Statement



A cops and robbers chase is set up as follows

1. Both the police car and the robber's can start from rest
2. The robbers have 1 km head start
3. The robber's van accelerate at 0.50 m/s
4. The police car accelerate at 0.60 m/s

Use famous 5 equations to answer the following
A. When will the speed of the cop car and the robber van be the same
B. When will the cops catch the robbers ?[/B]

Can someone please give an idea how to approach this answer. This would be very helpful if someone tell m ethe answer!
 
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You know that when they meet, the distance covered by the robber = the distance covered by the cops + 1000 metres, and the time at this point is equal for both.
You could say that :
( Based on the classic equation : s = ( u * t ) + ( ½ * a * t² ) )
½ * 0.6 * t² = ( ½ * 0.5 * t² ) + 1000
 
dean barry said:
You know that when they meet, the distance covered by the robber = the distance covered by the cops + 1000 metres, and the time at this point is equal for both.
You could say that :
( Based on the classic equation : s = ( u * t ) + ( ½ * a * t² ) )
½ * 0.6 * t² = ( ½ * 0.5 * t² ) + 1000
Dean, yet again you give too much help in one go. It would have been fine without that last line. Please stop doing this.