On the straight road, car a and car B move in the same direction. Car B moves in a straight line at a speed of 3 M / s. when car B is 4 m in front of car a, car a will leave the road At rest, it starts to make a uniform acceleration linear motion with an acceleration of 2 m / S2. When car a catches up with car B, it immediately makes a uniform deceleration linear motion with an acceleration of - 4 m / S2. How long will it take car B to catch up with car a again? | Math enthusiast | Mathematical art

On the straight road, car a and car B move in the same direction. Car B moves in a straight line at a speed of 3 M / s. when car B is 4 m in front of car a, car a will leave the road At rest, it starts to make a uniform acceleration linear motion with an acceleration of 2 m / S2. When car a catches up with car B, it immediately makes a uniform deceleration linear motion with an acceleration of - 4 m / S2. How long will it take car B to catch up with car a again?

The time for car a to catch up with car B is t
4+3t=2t²/2
t²-3t-4=0
t=4s
Car a takes 4S to catch up with car B
At this time, the velocity of a is v = at = 2 * 4 = 8m / s
Then, car B has to go through t to catch up with car a
3t=8t+at²/2
3t=8t-2t²
t=2.5s
It will take 2.5 seconds for car B to catch up with car a

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