REACTION TIMES AND DISTANCES

 


The purpose of this activity is to look at the effect of different activities on your driving response times, and the distance you travel during those times at different speeds.

 

A.    Measuring reaction time

 

1.     Use the formula d = ½ at2  , and solve for t, to find your reaction time when a = 981.2 cm/s2.

 

Distance ruler dropped before I grabbed it (cm)

Trial 1

Trial 2

Trial 3

Trial 4

Trial 5

Mean

Standard Error*

 

 

 

 

 

 

 

(Show your calculations here) (*Standard error = (standard deviation/sqrt(5)); use Excel to find the standard deviation)

 

 

 

 

2. Repeat #1, catching the meter stick while texting on a cel phone.

Reaction time (s)

Trial 1

Trial 2

Trial 3

Trial 4

Trial 5

Mean

Standard Error*

 

 

 

 

 

 

 

 

 

 

 

 

My normal reaction time is _______ seconds. My reaction time while texting is ________ seconds.

 

B.    Calculating the distance you travel at different speeds.

  1. Determine your reaction time during each situation.
    1. For example – your normal (just driving) reaction time is 0.88 seconds.  To find your reaction time while receiving a call on your cel phone, multiply your normal reaction time by 1.25. 
    2. So, 0.88s *1.25 = 1.12s.
    3. The directions for calculating each different reaction time are at the top of each data table.

 

  1. Convert each speed (mph) to speed (m/s) by going to http://www.convert-me.com/en/convert/speed.

 

  1. Calculate the distance by multiplying speed (in m/s) x (reaction time for that situation).

 

  1. Convert (the distance traveled in meters) to (the distance traveled in feet) by going to http://www.convert-me.com/en/convert/length.

 

C.     Graph all of your results on one graph using Excel.  Please make sure the legend is displayed!

 

D.    Answer the following questions:

a.     In general, what happens to the reaction distance as the speed increases?

b.     What happens to the reaction distance as the reaction time increases?

 


For just driving: My reaction time would be (my normal reaction time) = ______.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

 

For texting while driving, my reaction time is __________.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

 

For receiving a call on the cel phone, my reaction time is (1.25 x my usual reaction time) = ______.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

 

For placing a call on the cel phone, my reaction time is (1.341 x my usual reaction time) = ______.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

 

For talking on the cel phone, my reaction time is (1.073 x my usual reaction time) = _____.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

 


For adjusting the radio/CD player, my reaction time is (1.011 x my usual reaction time) = ______.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

 

For eating/drinking (non-alcoholic) while driving, my reaction time is (1.128 x my usual reaction time) = ______.

Description

Speed (mph)

Speed (m/s)

Distance traveled (m)

Distance traveled (ft)

Backing out of the driveway

5

 

 

 

In slow traffic

10

 

 

 

School zone

20

 

 

 

On 33rd street

30

 

 

 

On Vine street

35

 

 

 

South of town on 183

65

 

 

 

On I-70

70

 

 

 

Speeding on I-70

80

 

 

 

Being stupid

90

 

 

 

Beyond stupidity

120

 

 

 

*reaction time delays adapted from  http://ppc.uiowa.edu/driving-assessment/2001/Summaries/PostSession1/Tokunaga_roberto_abraham.pdf

 

Remember – these are just the distances youÕll travel BEFORE you hit the brakes!

 

Next, weÕll deal with acceleration and how long itÕll take your brakes to bring you to a stop.