Chapter 1: Using apparatus
or, expressed in symbols: v=
d t
The standard unit for speed in the SI system of units is m s−1.
Equipment You will need:
E
• cylinder • wooden board • stand • boss • clamp • metre rule • protractor • stopwatch • book or pencil case to act as a barrier at the bottom of the ramp.
Safety considerations
M PL
• Make sure you have read the Safety advice at the beginning of this book and listen to any advice from your teacher before carrying out this investigation. • Use a book or a pencil case to stop the cylinder after it has reached the bottom of the wooden board.
Part 1: Investigating reaction time Method
1 Set your stopwatch to zero.
2 Switch the stopwatch on and off as quickly as you can and record the reading. 3 Repeat this reading and record the three values in Table 1.11 in the Results section.
Results
t2 / s
t3 / s
SA
t1 / s
Table 1.11
Data analysis
a Calculate the mean value of t.
t = …………… s
Evaluation b Figure 1.10 shows a reading of 1.44 seconds on a stopwatch.
Figure 1.10 Original material © Cambridge University Press
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