LEARNING INTENTIONS
In this chapter you will learn how to:
- recognise random, systematic and zero errors
- calculate uncertainties in measurements made with a range of instruments
- distinguish between precision and accuracy
- estimate absolute uncertainties and combine uncertainties when quantities are added, subtracted, multiplied and divided
- set up apparatus, follow instructions and make a variety of measurements
- present data in an adequate table, produce best fit straight-line graphs and obtain the intercept and gradient
- use readings to draw conclusions from an experiment and to test a relationship
- identify limitations in an experiment and identify the main sources of uncertainty
- suggest changes to an experiment to improve accuracy and extend an investigation.
BEFORE YOU START
- What are physical properties of materials?
- What quantities do all these instruments measure: protractor, $30 cm$ ruler, metre rule, micrometer screw gauge, calipers, newton-meter, balance, measuring cylinder, thermometer, stopwatch, ammeter and voltmeter?
- Can you suggest, for each instrument in the list, what is its range and its smallest scale division, and suggest a simple experimental problem in using it?
Throughout your A Level physics course, you will develop your skills in practical work, and they will be assessed at both AS & A Level. This chapter outlines the skills you will develop in the first year of the course; it includes some activities to test your understanding as you go along.
The sciences differ from most other subjects in that they involve not only theory but also practical work.
The very essence of science is that theory can be tested by practical experiment. So, the ability to carry out practical exercises in a logical and scientific manner is essential.