A motorcycle is following a car that is traveling at constant speed on a straight highway. Initially, the car and the motorcycle are both traveling at the same speed of 19.0m/s , and the distance between them is 52.0m . After t1 = 5.00s , the motorcycle starts to accelerate at a rate of 5.00m/s2. How long does it take from the moment when the motorcycle starts to accelerate until it catches up with the car? In other words, find t2−t1

4 answers

Dc = 19t = Distance of the car after t1.
Dm = Vo*t + 0.5a*t^2 = Distance of motorcycle after t1.

Dm = Dc + 52
Vo*t + 0.5a*t^2 = 19t + 52
19*t + 2.5*t^2 = 19t + 52
19t - 19t + 2.5*t^2 = 52
t^2 = 20.8
t = 4.56 s.

So the motorcycle caught-up 4.56 s after
it started to accelerate.
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4.56 s
A relative density bottle weight 20g when empty, 80g when field with water and 100g when with a liquid. Fine the relative density of liquid.