Question

A tortoise can run with a speed of 0.12 m/s, and a hare can run 20 times as fast. In a race, they both start at the same time, but the hare stops to rest for 1.0 minutes. The tortoise wins by a shell (30 cm).
(a) How long does the race take?
(b) What is the length of the race?

Answers

drwls
(a) Re
drwls
Sorry, my computer is acting up.
drwls
Write equations for distances travelled vs time for each animal. Assume the hare pauses once, for 60 seconds, during the race.

Set the distance travelled by the tortoise (X1) equal to the distance travelled by the hare (X2) PLUS 0.3 meters.

X1 = 0.12 t meters

X2 = 2.4 (t - 60)

X1 - X2 = 0.12t -2.4t + 144 = 0.3

Solve for t.

143.7 = 2.28 t

t = 63.026 seconds

Using that t, compute X1(t)

X1 = 7.563 m
X2 = 7.263 m
Vidhu
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