Wave P and wave Q travel along the same stretched string. At a certain instant their displacement–distance graphs show:
• For wave P, the distance between two consecutive crests is 6cm and each crest is 2cm above the mean position.
• For wave Q, the distance between two consecutive crests is 4cm and each crest is 3cm above the mean position.
A stopwatch records that, for the same particle of the string, the time interval between successive crests of wave P passing is 0.03s, while for wave Q it is 0.02s.
(i) Calculate the speed of wave P.
(ii) Calculate the speed of wave Q.
(iii) Which wave has the greater amplitude?