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You are doing an experiment to determine your reaction time. Your friend holds a ruler. You place your fingers near the sides of the lower part of the ruler without touching it. The friend drops the ruler without warning you. You catch the ruler after it falls 12.9 cm. What was your reaction time?

User Mpaolini
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1 Answer

4 votes

Answer:

0.162 s

Step-by-step explanation:

To determine your reaction time, we can use the equation:

⇒ d = (1/2)at^2

  • where d is the distance the ruler falls, a is the acceleration due to gravity (9.8 m/s^2), and t is the time it takes for you to react and catch the ruler.

First, we need to convert the distance the ruler falls from centimeters to meters:

⇒ d = 12.9 cm = 0.129 m

Next, we can rearrange the equation to solve for t:

⇒ t = sqrt(2d/a)

⇒ t = sqrt(2(0.129 m)/(9.8 m/s^2))

⇒ t = sqrt(0.0264 s^2)

⇒ t = 0.162 s

Therefore, your reaction time was approximately 0.162 seconds.

User Wen Xu Li
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