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3 years ago

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A racing car is travelling at 70 m/s and accelerates at -14 m/s2. What would the car’s speed be after 3 s?

1 answer:

Leno4ka [110]3 years ago

3 0

<h3><u>Question</u><u>:</u></h3>

A racing car is travelling at 70 m/s and accelerates at -14 m/s^2. What would the car’s speed be after 3 s?

<h3><u>Statement:</u></h3>

A racing car is travelling at 70 m/s and accelerates at -14 m/s^2.

<h3><u>Solution</u><u>:</u></h3>

Initial velocity (u) = 70 m/s
Acceleration (a) = -14 m/s^2
Time (t) = 3 s
Let the velocity of the car after 3 s be v m/s
By using the formula,

v = u + at, we have

$v = 70 + ( - 14)(3) \\ = > v = 70 - 42 \\ = > v = 28$

So, the velocity of the car after 3 s is 28 m/s.

<h3><u>Answer:</u></h3>

The car's speed after 3 s is 28 m/s.

Hope it helps

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