Dynamics- collision of cars problem

AI Thread Summary
The discussion centers on a dynamics problem involving two cars, A and B, both initially traveling at 98 ft/s, with car A tailgating car B. When car B begins to decelerate at 20 ft/s² due to an accident ahead, car A is only 22.5 ft behind and takes 0.5 seconds to apply its brakes, decelerating at 30 ft/s². The key point of confusion is whether car A applies brakes immediately or after the 0.5 seconds. The calculations focus on determining the time until collision and the relative speed at impact. The resolution of this problem hinges on clarifying the timing of car A's braking response.
chiraganand
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The problem is like this
Assume both cars A and B are intially traveling to the right at 98 ft/s. Car A is tailgating leaving very little room between car A and car B. At that instant driver of car B notices a n accident and starts to break witha deceleration of 2o ft/s^2. By the time the driver of car A notices the distance betwwen them has reduced to 22.5 ft and the velocity of car B is slowed down to 78 ft/s. Assume that the driver of car A immediately puts the brakes and it takes him only 0.5 s to apply breaks. The car decelerates with 30 ft/s^2. Calculate when collision occurs and relative speed of collision.

I have already solved the problem. attaching the solution. can anyone let me know if i am correct or wrong
 

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chiraganand said:
The problem is like this
Assume that the driver of car A immediately puts the brakes and it takes him only 0.5 s to apply brakes. /QUOTE]

Which is it? Does he immediately apply the brakes or does it take him 0.5s to apply the brakes?
 
He applies the break after 0.5 s
 
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