Topic 1: Measurements and their errors

Question 1

accuracy

Answer 1

How close the measurement is to the true value.

Question 2

precision

Answer 2

How close the measurement is to the mean value, giving indication of the magnitude of random errors.

Question 3

random error

Answer 3

unpredictable variation between measurements, reduced by taking repeat values

Question 4

systematic error

Answer 4

causes all readings to differ from true value by a fixed amount, cannot be corrected by repeat readings

Question 5

repeatable

Answer 5

same experimenter can repeat the measurement using the same method and equipment and obtain the same value

Question 6

reproduceable

Answer 6

can be repeated by a different experimenter using a different method and apparatus and still obtain the same results

Question 7

resolution

Answer 7

the smallest change in a quantity that causes a visible change in the reading that a measuring instrument records

Question 8

unceartainty

Answer 8

the interval that a value is said to lie within, with a given level of confidence