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3 years ago

15

Near the end of a marathon race, the first two runners are separated by a distance of 45.6 m. The front runner has a velocity of

3.1 m/s, and the second a velocity of 4.65 m/s. How many seconds earlier will the second runner reach the finish line if the front runner is 250 m from the finish line in seconds?

1 answer:

morpeh [17]3 years ago

3 0

Answer:17.08 s

Explanation:

Given

distance between First and second Runner is 45.6 m

speed of first runner $(v_1)$ =3.1 m/s

speed of second runner $(v_2)$ =4.65 m/s

Distance between first runner and finish line is 250 m

Second runner need to run a distance of 250+45.6=295.6 m

Time required by second runner $t=\frac{295.6}{4.65}=63.56 s$

time required by first runner to reach finish line $=\frac{250}{3.1}=80.64 s$

Thus second runner reach the finish line 80.64-63.56=17.08 s earlier

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