Question

Can someone help me with this problem due tomorrow?

Two cyclists race with nearly uniform speed on a 500 m course. The blue bicycle crosses the finish life 2.0 seconds ahead of the red bicycle. If the red cycle maintained an average speed of 10 m/s, what was the average speed of the blue bicycle?​

Answer 1

Speed = distance travelled / time spent

That means to find out the speed of blue, we need distance travelled (which is 500m) and time spent.

Now, we do now we arrived 2 seconds before the red bicycle. Now, how do we find the time spent by the red bicycle?

Well, we can change some terms in the first equation:

Speed * time spent = distance travelled
Time spent = distance travelled / speed

That means the red bicycle took
500m / 10 m/s = 50s for the course.

Therefore the blue bicycle took 50s-2s=48s for the race.

Therefore, blue’s speed was:
Speed = 500m/48s
Which is around 10.42 m/s.