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MakcuM [25]
3 years ago
10

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?

Physics
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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