Required practical: nervous system + ruler

Question 1

What is needed for this practical?

Answer 1

2 people and a ruler

Question 2

Step 1

Answer 2

Person 1 sits on a chair with good upright posture

Question 3

Step 2

Answer 3

Person 1 places forearm of their dominant arm across the table with hand hanging over edge to catch the ruler

Question 4

Step 3

Answer 4

Person 2 holds metre ruler vertically so the 0cm mark is between their thumb and index finger

Question 5

Step 4

Answer 5

Person 2 signals they will drop the ruler soon then does so at a random time
Person 1 catches it as soon as possible

Question 6

Step 5

Answer 6

Measure where person 1 caught the ruler based on where their thumb is

Question 7

Step 6

Answer 7

Repeat test several times and calculate mean then convert to reaction time using a conversion table

Question 8

Step 7

Answer 8

Person 2 and 1 switch places

Question 9

Independent variable

Answer 9

Many other that we could investigate:
Person 1 having reaction time tested vs person 2
Number of tries/ practise had
Dominant hand/ non dominant
Effect of certain chemicals eg caffeine

Question 10

Dependent variable

Answer 10

Reaction time

Question 11

Control variables

Answer 11

Starting distance between thumb + first finger on the ruler
Measure ruler length at the top of the thumb when caught
Keep lighting and background noise same

Question 12

How do we measure effect of caffeine on reaction time?

Answer 12

Compare normal reaction time to after drinking some cola
Problem is other chemicals in cola?
So use caffeine free cola and also compare that