1. Measurements

Question 1

state what is meant by a scalar quantity and vector quantity

Answer 1

scalar has magnitude only

vector has magnitude and direction

Question 2

state how random errors are reduced

Answer 2

take average of several readings

Question 3

explain why precision in the value of resistivity is improved using a micrometer screw gauge rather than a metre rule to measure the diameter of a wire

Answer 3

precision is determined by the range in measurements
metre rule measures to +/- 1mm and micrometer to +/- 0.01mm
so there is less percentage uncertainty

Question 4

explain the difference between accuracy and precision

Answer 4

accuracy: determined by closeness of values to the true value
precision: determined by the range of the values

Question 5

describe the effects, one in each case, of systematic errors and random errors when using a micrometer screw gauge to take readings for the diameter of a wire

Answer 5

systematic: reading is larger or smaller than the true reading by a constant amount
random: scatter in readings about the true reading