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3 years ago

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A car travels from point a to point b, moving in the same direction but with a non-constant speed. the first half of the distanc

e, the car travels with a speed v_1v 1 . the remaining part of the way, the car travels half the time with a speed v_2v 2 and half the time with a speed v_3v 3 . what is the average speed over the entire journey

2 answers:

Naddik [55]3 years ago

6 0

You have to devide and add evreythuy butthe answer is 464

Ira Lisetskai [31]3 years ago

5 0

Answer:

$\frac{4v_1v_2v_3}{2v_2v_3+v_1v_2+v_1v_2}$

Explanation:

The average speed is given by:

$v_{avg}= \frac{\text{total distance}}{\text{total time taken}}$

let the total distance be d

time taken in first part of the journey= t₁

$t_1 = \frac{d/2}{v_1}$

time taken in second part of the journey= t₂

$t_2 = \frac{d/4}{v_2}$

time taken in third part of the journey= t₃

$t_3 = \frac{d/4}{v_3}$

$v_{avg}= \frac{d}{t_1+t_2+t_3}=\frac{d}{\frac{d/2}{v_1}+\frac{d/4}{v_2}+\frac{d/4}{v_3}}$

$v_{avg}=\frac{4v_1v_2v_3}{2v_2v_3+v_1v_2+v_1v_2}$

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