Explain Why Average Time Provide A More Realistic Reaction Time Lab Report
PHYSICS LAB
REACTION TIMES
Mr. Brown
Name: Jisoo Lee
Partner: Seongwook Youn
Date: 5/9/17
Purpose: To measure human body’s reaction time to respond and act on unexpected events.
Apparatus: The following materials are required for this lab:
US dollar bill (new)
A meter stick
Diagram:
Procedure: Part A
To be done in groups of two. One of the two will hold a US dollar bill vertically. The partner will lay their arm on a table and stick their hand out of the edge of a table. The partner will have only their index finger and thumb out while having the dollar bill in between. The person holding the dollar bill will drop the money without any warning, but should not add any force by pushing as the person should only ‘drop’ the …show more content…
dollar bill. As soon as the dollar bill is dropped, the partner should try and catch the dollar bill with their thumb and index finger only. Each person will attempt three times to catch the dollar bill, and they will succeed if they catch the dollar bill at least two out of three tries.
Part B
To be done in groups of two. One of the two will hold a meter stick by the top end and the partner will lay their arm on a table. The partner with their arm laying on the table will have only have their index finger and thumb out, having a ruler in between. The drops of the ruler will be constant to 20 cm from the bottom end of the meter stick. When ready, the person holding the meter stick will drop it without any notice, and the other person will catch it with their thumb and index finger. Both partners will have 10 trials for both of their hands. Both partners will have the catching point rounded to the nearest half centimeter.
Data
Table 1: Jisoo’s Left Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
52.0
32.0
0.26
2
20.0
54.0
34.0
0.26
3
20.0
55.0
35.0
0.27
4
20.0
43.0
23.0
0.22
5
20.0
38.0
18.0
0.19
6
20.0
34.0
14.0
0.17
7
20.0
51.0
31.0
0.25
8
20.0
79.0
59.0
0.35
9
20.0
35.0
15.0
0.17
10
20.0
36.0
16.0
0.18
Table 2: Jisoo’s Right Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
38.0
18.0
0.19
2
20.0
43.0
23.0
0.22
3
20.0
51.0
31.0
0.25
4
20.0
35.0
15.0
0.17
5
20.0
35.0
15.0
0.17
6
20.0
37.0
17.0
0.19
7
20.0
49.0
29.0
0.24
8
20.0
36.0
16.0
0.18
9
20.0
33.0
13.0
0.16
10
20.0
40.0
20.0
0.20
Table 3: Seongwook’s Left Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
42.0
22.0
0.21
2
20.0
65.0
45.0
0.30
3
20.0
35.0
15.0
0.17
4
20.0
28.0
8.0
0.13
5
20.0
45.0
25.0
0.23
6
20.0
28.0
8.0
0.13
7
20.0
29.0
9.0
0.14
8
20.0
28.0
8.0
0.13
9
20.0
27.0
7.0
0.12
10
20.0
30.0
10.0
0.14
Table 4: Seongwook’s Right Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
29.0
9.0
0.14
2
20.0
35.0
15.0
0.17
3
20.0
35.0
15.0
0.17
4
20.0
30.0
10.0
0.14
5
20.0
46.0
26.0
0.23
6
20.0
31.0
11.0
0.15
7
20.0
39.0
19.0
0.20
8
20.0
38.0
18.0
0.19
9
20.0
38.0
18.0
0.19
10
20.0
46.0
26.0
0.23
Analysis:
Calculating Time for Each Individual Trial (Ex: Trial #1 in Table #1)
Time (t)
?
Displacement (d)
-0.32 m
Initial Velocity (vi)
0 m/s
Final Velocity (vf)
N/A
Acceleration (a)
-9.8 ms-2
Using the formula of:
displacement = initial velocity x time + (acceleration x time2)/2
As initial velocity is 0, the equation becomes
displacement = 0 + (acceleration x time2)/2
displacement = (acceleration x time2)/2
2 x displacement = (acceleration x time2)
(2 x displacement)/ acceleration = time2
time = square root ((2 x displacement)/ acceleration)
Using this formula for trial #1 in table #1,
Calculating Average Time for Each Hand (Using Table 1 as Example)
Formula -> Average time = (sum of all times from 10 trials) / 10
(0.26+0.26+0.27+0.22+0.19+0.17+0.25+0.35+0.17+0.18) / 10 = 0.232
Hence, the average time is 0.23 (3 sig figs) in table 1.
Name and Hand
Average Reaction Time (seconds)
Jisoo’s Left Hand
0.23
Jisoo’s Right Hand
0.20
Seongwook’s Left Hand
0.17
Seongwook’s Right Hand
0.18
Why Average Time Provide A More Realistic Reaction Time?
In this experiment, we can determine that human reaction time is not consistent throughout the entire experiment. There are ranges and have many deviations in data we have retrieved. As the data tables have many different values, it is hard to determine which value should be chosen. Also, as the median value of the data does not always mean it’s the most accurate data, it is most logical to calculate the average reaction time as the deviations can be cancelled out. To conclude, using the average value will be more accurate since the accuracy of the data will increase.
Percentage Error
After research, I have discovered that the average human reaction time is 0.25 for visual stimulus.
Calculating Percentage Error
%Error = Experimental value - Theoretical valueTheoretical value x 100
Using my left hand’s average reaction time as an example, which was 0.23 seconds, calculating the percentage error for this experiment, I have retrieved the following data.
%Error = 0.23 - 0.250.25 x 100
= …show more content…
8%
Name and Hand
Percentage Error
Jisoo’s Left Hand
8%
Jisoo’s Right Hand
20%
Seongwook’s Left Hand
32%
Seongwook’s Right Hand
28%
According to the data table above, my left hand is 8% faster than the theoretical value while my right hand is 20% faster than the theoretical value. My partner, Seongwook, has his left hand 32% faster than the theoretical value while his right hand is 28% faster than the theoretical value.
Bill Enlargement
In part A, I was unable to catch any of the dollar bills. To increase my possibilities of catching the dollar bill to the nearest 100%, it was inevitable for me to enlarge the bills. Hence, this is the following procedure I have used to acquire the percentage of enlargement for my dollar bill.
Formula:
Bill Enlargement: (Average Distance for Left Hand + Average Distance for Right HandLength of Dollar bill x 2 x 100 ) + 100
Using the formula,
(19.8 + 19.72 x15.5x 100) + 100 = 227%
According to my calculations, if I enlarge the dollar bill by 227%, I should be able to catch the dollar bills easily. However, some of my data have outliers which is 59 cm for my case, are way above the average distance of 19.75. To ensure I get my value to 100%, I will also use my maximum value of the fall. Hence, this will be the formula used.
Formula: (2 x Maximum DistanceLength of Dollar bill x 2 x 100) + 100
Using the formula,
(2 x5915.5 x 2 x 100) + 100 = 481%
481/250 = 1.924
Hence, I will first enlarge the bill by 250%, then enlarge the enlarged note by 192.4%, I would’ve got the dollar bill which would’ve ensured me 100% success if was used in my 20 trials combined.
Conclusions:
Judging from data I have collected throughout the experiment, I can safely assume my experiment was a success as my calculations are accurate to average values.
This proves that my average reaction time values are plausible and makes sense, which again is proved through one of the kinematics equation. However, there may also be also be a few random and systematic errors which may have impacted my data values.
Lists of Sources of Errors
Suggested Improvements
The kinematics equation I have used only applies when there is no air resistance.
If possible, do in a place with no air resistance, such as vacuumed area if possible.
Air conditioner in the class may have impacted the direction of the fall (not completely straight)
If possible, do in an area without any air movements or possible turn off both fan and air conditioner.
The procedure did not tell us how much our index and thumb should be apart as sometimes the distance varied a lot which can drastically impact the result.
State how much distance there should be between the thumb and the index finger and make sure have that constant throughout the experiment.
Bibliography
“Experiment: How Fast Your Brain Reacts To Stimuli.” Experiment: How Fast Your Brain Reacts To Stimuli,
backyardbrains.com/experiments/reactiontime.
REACTION TIMES
Mr. Brown
Name: Jisoo Lee
Partner: Seongwook Youn
Date: 5/9/17
Purpose: To measure human body’s reaction time to respond and act on unexpected events.
Apparatus: The following materials are required for this lab:
US dollar bill (new)
A meter stick
Diagram:
Procedure: Part A
To be done in groups of two. One of the two will hold a US dollar bill vertically. The partner will lay their arm on a table and stick their hand out of the edge of a table. The partner will have only their index finger and thumb out while having the dollar bill in between. The person holding the dollar bill will drop the money without any warning, but should not add any force by pushing as the person should only ‘drop’ the …show more content…
dollar bill. As soon as the dollar bill is dropped, the partner should try and catch the dollar bill with their thumb and index finger only. Each person will attempt three times to catch the dollar bill, and they will succeed if they catch the dollar bill at least two out of three tries.
Part B
To be done in groups of two. One of the two will hold a meter stick by the top end and the partner will lay their arm on a table. The partner with their arm laying on the table will have only have their index finger and thumb out, having a ruler in between. The drops of the ruler will be constant to 20 cm from the bottom end of the meter stick. When ready, the person holding the meter stick will drop it without any notice, and the other person will catch it with their thumb and index finger. Both partners will have 10 trials for both of their hands. Both partners will have the catching point rounded to the nearest half centimeter.
Data
Table 1: Jisoo’s Left Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
52.0
32.0
0.26
2
20.0
54.0
34.0
0.26
3
20.0
55.0
35.0
0.27
4
20.0
43.0
23.0
0.22
5
20.0
38.0
18.0
0.19
6
20.0
34.0
14.0
0.17
7
20.0
51.0
31.0
0.25
8
20.0
79.0
59.0
0.35
9
20.0
35.0
15.0
0.17
10
20.0
36.0
16.0
0.18
Table 2: Jisoo’s Right Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
38.0
18.0
0.19
2
20.0
43.0
23.0
0.22
3
20.0
51.0
31.0
0.25
4
20.0
35.0
15.0
0.17
5
20.0
35.0
15.0
0.17
6
20.0
37.0
17.0
0.19
7
20.0
49.0
29.0
0.24
8
20.0
36.0
16.0
0.18
9
20.0
33.0
13.0
0.16
10
20.0
40.0
20.0
0.20
Table 3: Seongwook’s Left Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
42.0
22.0
0.21
2
20.0
65.0
45.0
0.30
3
20.0
35.0
15.0
0.17
4
20.0
28.0
8.0
0.13
5
20.0
45.0
25.0
0.23
6
20.0
28.0
8.0
0.13
7
20.0
29.0
9.0
0.14
8
20.0
28.0
8.0
0.13
9
20.0
27.0
7.0
0.12
10
20.0
30.0
10.0
0.14
Table 4: Seongwook’s Right Hand Reaction Time
Trial #
Starting Point (±0.5 cm)
Catch Point (±0.5 cm)
Distance (±1 cm)
Time (seconds)
1
20.0
29.0
9.0
0.14
2
20.0
35.0
15.0
0.17
3
20.0
35.0
15.0
0.17
4
20.0
30.0
10.0
0.14
5
20.0
46.0
26.0
0.23
6
20.0
31.0
11.0
0.15
7
20.0
39.0
19.0
0.20
8
20.0
38.0
18.0
0.19
9
20.0
38.0
18.0
0.19
10
20.0
46.0
26.0
0.23
Analysis:
Calculating Time for Each Individual Trial (Ex: Trial #1 in Table #1)
Time (t)
?
Displacement (d)
-0.32 m
Initial Velocity (vi)
0 m/s
Final Velocity (vf)
N/A
Acceleration (a)
-9.8 ms-2
Using the formula of:
displacement = initial velocity x time + (acceleration x time2)/2
As initial velocity is 0, the equation becomes
displacement = 0 + (acceleration x time2)/2
displacement = (acceleration x time2)/2
2 x displacement = (acceleration x time2)
(2 x displacement)/ acceleration = time2
time = square root ((2 x displacement)/ acceleration)
Using this formula for trial #1 in table #1,
Calculating Average Time for Each Hand (Using Table 1 as Example)
Formula -> Average time = (sum of all times from 10 trials) / 10
(0.26+0.26+0.27+0.22+0.19+0.17+0.25+0.35+0.17+0.18) / 10 = 0.232
Hence, the average time is 0.23 (3 sig figs) in table 1.
Name and Hand
Average Reaction Time (seconds)
Jisoo’s Left Hand
0.23
Jisoo’s Right Hand
0.20
Seongwook’s Left Hand
0.17
Seongwook’s Right Hand
0.18
Why Average Time Provide A More Realistic Reaction Time?
In this experiment, we can determine that human reaction time is not consistent throughout the entire experiment. There are ranges and have many deviations in data we have retrieved. As the data tables have many different values, it is hard to determine which value should be chosen. Also, as the median value of the data does not always mean it’s the most accurate data, it is most logical to calculate the average reaction time as the deviations can be cancelled out. To conclude, using the average value will be more accurate since the accuracy of the data will increase.
Percentage Error
After research, I have discovered that the average human reaction time is 0.25 for visual stimulus.
Calculating Percentage Error
%Error = Experimental value - Theoretical valueTheoretical value x 100
Using my left hand’s average reaction time as an example, which was 0.23 seconds, calculating the percentage error for this experiment, I have retrieved the following data.
%Error = 0.23 - 0.250.25 x 100
= …show more content…
8%
Name and Hand
Percentage Error
Jisoo’s Left Hand
8%
Jisoo’s Right Hand
20%
Seongwook’s Left Hand
32%
Seongwook’s Right Hand
28%
According to the data table above, my left hand is 8% faster than the theoretical value while my right hand is 20% faster than the theoretical value. My partner, Seongwook, has his left hand 32% faster than the theoretical value while his right hand is 28% faster than the theoretical value.
Bill Enlargement
In part A, I was unable to catch any of the dollar bills. To increase my possibilities of catching the dollar bill to the nearest 100%, it was inevitable for me to enlarge the bills. Hence, this is the following procedure I have used to acquire the percentage of enlargement for my dollar bill.
Formula:
Bill Enlargement: (Average Distance for Left Hand + Average Distance for Right HandLength of Dollar bill x 2 x 100 ) + 100
Using the formula,
(19.8 + 19.72 x15.5x 100) + 100 = 227%
According to my calculations, if I enlarge the dollar bill by 227%, I should be able to catch the dollar bills easily. However, some of my data have outliers which is 59 cm for my case, are way above the average distance of 19.75. To ensure I get my value to 100%, I will also use my maximum value of the fall. Hence, this will be the formula used.
Formula: (2 x Maximum DistanceLength of Dollar bill x 2 x 100) + 100
Using the formula,
(2 x5915.5 x 2 x 100) + 100 = 481%
481/250 = 1.924
Hence, I will first enlarge the bill by 250%, then enlarge the enlarged note by 192.4%, I would’ve got the dollar bill which would’ve ensured me 100% success if was used in my 20 trials combined.
Conclusions:
Judging from data I have collected throughout the experiment, I can safely assume my experiment was a success as my calculations are accurate to average values.
This proves that my average reaction time values are plausible and makes sense, which again is proved through one of the kinematics equation. However, there may also be also be a few random and systematic errors which may have impacted my data values.
Lists of Sources of Errors
Suggested Improvements
The kinematics equation I have used only applies when there is no air resistance.
If possible, do in a place with no air resistance, such as vacuumed area if possible.
Air conditioner in the class may have impacted the direction of the fall (not completely straight)
If possible, do in an area without any air movements or possible turn off both fan and air conditioner.
The procedure did not tell us how much our index and thumb should be apart as sometimes the distance varied a lot which can drastically impact the result.
State how much distance there should be between the thumb and the index finger and make sure have that constant throughout the experiment.
Bibliography
“Experiment: How Fast Your Brain Reacts To Stimuli.” Experiment: How Fast Your Brain Reacts To Stimuli,
backyardbrains.com/experiments/reactiontime.