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3 years ago

7

In a 100-m race, the winner is timed at 11.2 s. The second-place finisher’s time is 11.6 s. How far is the second-place finisher

behind the winner when she crosses the finish line? Assume the velocity of each runner is constant throughout the race.

1 answer:

Veronika [31]3 years ago

3 0

Answer:

d = 3.45 m

Explanation:

given,

distance, d = 100 m

time of winner = 11.2 s

time of finisher = 11.6 s

distance between them when winner finish race

speed of winner

$s_1 = \dfrac{d}{t_1}$

$s_1 = \dfrac{100}{11.2}$

s₁ = 8.93 m/s

speed of runner up

$s_2 = \dfrac{d}{t_2}$

$s_2= \dfrac{100}{11.6}$

s₂= 8.62 m/s

difference in time = t₂ - t₁ = 11.6 - 11.2 = 0.4 s

distance between them

d = s₂ x t

d = 8.62 x 0.4

d = 3.45 m

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