A student investigated the reflection of microwaves by a flat metal plate using a microwave transmitter and receiver. For four different angles of incidence, they measured the angle of reflection (corresponding to the direction of maximum detected signal strength) over four repeated trials.
Their results are shown in the table below:
Angle of incidenceTest 1Test 2Test 3Test 420∘18∘22∘19∘21∘30∘28∘33∘31∘28∘40∘38∘42∘43∘37∘50∘55∘45∘53∘47∘ \begin{array}{|c|c|c|c|c|} \hline \text{Angle of incidence} & \text{Test 1} & \text{Test 2} & \text{Test 3} & \text{Test 4} \\ \hline 20^\circ & 18^\circ & 22^\circ & 19^\circ & 21^\circ \\ \hline 30^\circ & 28^\circ & 33^\circ & 31^\circ & 28^\circ \\ \hline 40^\circ & 38^\circ & 42^\circ & 43^\circ & 37^\circ \\ \hline 50^\circ & 55^\circ & 45^\circ & 53^\circ & 47^\circ \\ \hline \end{array} Angle of incidence20∘30∘40∘50∘Test 118∘28∘38∘55∘Test 222∘33∘42∘45∘Test 319∘31∘43∘53∘Test 421∘28∘37∘47∘What type of scientific error has caused the measured angles of reflection to have a range of values for each angle of incidence?
Suggest one practical reason why this error occurred during this investigation.
Estimate the uncertainty in the angle of reflection when the angle of incidence is 50∘50^\circ50∘. Show how you determine your estimate.
Explain how the data in the table supports the conclusion that the angle of incidence is equal to the angle of reflection, using calculated values from the table to support your explanation.
State one change the student should make to the apparatus if they want to use the same method to investigate diffuse reflection.
14 exam-style questions on AQA GCSE Physics 6.1 Waves in air, fluids and solids, covering 6.1.1 Transverse and longitudinal waves, 6.1.2 Properties of waves, 6.1.3 Reflection of waves, 6.1.4 Sound waves (HT only), and 6.1.5 Waves for detection and exploration (HT only). Each one has a worked solution and a mark scheme showing where the marks go.