Question

Measure Your Reaction Time Here's something you can try at home-an experiment to measure your reaction time. Have a friend hold a ruler by one end, letting the other end hang down vertically. At the lower end, hold your thumb and index finger on either side of the ruler, ready to grip it. Have your friend release the ruler without warning. Catch it as quickly as you can. If you catch the ruler 6.4 cm (~2.5 inches) from the lower end, what is your reaction time?

Answer 1

0.114s

Step-by-step explanation:

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The reaction time is simply how long it takes the ruler to fall 6.4 cm.

For this problem, all you gotta do is convert your units and then plug them into a kinematic equation for t (time).

{*0.01 the conversion from cm to m}

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Units:

Δx (change in x) or d = 6.4 cm = 0.064m

Vi = 0 m/s

a = 9.81 m/s^2

t = ?

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`d = Vi * t + (1)/(2) *a*t^(2)`

(0.064) = 0 * t + 1/2 * (9.81) * t^2

↓

0.064 = 1/2 * (9.81) * t^2

↓

0.064 = 4.905 * t^2

↓

0.01304791 = t^2

↓

t = 0.114s

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Your reaction time is 0.114s

Answer 2

Step-by-step explanation:

The reaction time will be equal to the time the ruler takes to fall by 6.4 cm .

the ruler is falling with acceleration due to gravity which is equal to

9.8 m /s²

S = ut + 1/2gt²

s is distance of fall , u is initial velocity , t is time and g is acceleration due to gravity .

6.4 = 0 + 1/2 x 9.8 t²

t = 1.14 s .

So reaction time is 1.14 s .