A car is waiting for the green light at the intersection. When the green light is on, the car starts to run at an acceleration of 3m / SS. Just at this time, a bicycle comes at a constant speed of 6m / s and drives past the car from behind (1) After the car starts, how long does it take before catching up with the bicycle? What is the distance between the two cars at this time? (2) When does the car catch up with the bike? What's the speed of the car at this time?

A car is waiting for the green light at the intersection. When the green light is on, the car starts to run at an acceleration of 3m / SS. Just at this time, a bicycle comes at a constant speed of 6m / s and drives past the car from behind (1) After the car starts, how long does it take before catching up with the bicycle? What is the distance between the two cars at this time? (2) When does the car catch up with the bike? What's the speed of the car at this time?

(1) When the car accelerates to 6m / s, the distance between the two cars is the farthest
V car = at, a = 3, t = V car / a = 6 / 3 = 2S
S car = 1 / 2att = 0.5 * 3 * 2 * 2 = 6M
S Bicycle = 6 * 2 = 12m
Maximum distance = 12-6 = 6M
(2) From the start of the car, if you catch up with the bicycle, it means that the distance is the same after T seconds, that is
S car = s bike
1 / 2att = vt
1/2*3*t=6
t=4s
V car = at = 3 * 4 = 12m / S