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10 votes
Suppose that you are riding your bike downtown Campbell at a speed of12 m/s and you see a red light ahead. You decrease your speed over adistance of 40 m and come to a complete stop. What is your accelerationduring this time?

User Aydin Hassan
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1 Answer

20 votes
20 votes

Answer: The acceleration is - 1.8 m/s^2

Step-by-step explanation:

From the information given,

initial velocity of bike, u = 12 m/s

final velocity of bike, v = 0 because the bike came to a complete stop

distance traveled, s = 40 m

We want to find the acceleration, a

We would apply the the newton's equation of motion below

v^2 = u^2 + 2as

By substituting the given values into the equation,

0^2 = 12^2 + 2 x a x 40

0 = 144 + 80a

Subtracting 144 from both sides, it becomes

0 - 144 = 144 - 144 + 80a

- 144 = 80a

80a = - 144

Dividing both sides by 80,

80a/80 = - 144/80

a = - 1.8 m/s^2

The acceleration is - 1.8 m/s^2

User Seffix
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