Question 1
What, to two
significant figures, are the period, the frequency and the amplitude of the
wave represented by the graph?
period
/ s frequency / Hz amplitude / m
A 0.0027 370
0.0067
B 0.0031 320
0.013
C 0.0035 290
0.0067
D 0.0042
240 0.013
Reference: Past Exam Paper – June 2014 Paper 12 Q22
Solution:
Answer: C.
A graph of displacement against time
is given. The y-axis gives displacement in ‘m’ and the x-axis gives time in ‘ms’.
Period can be directly obtained from
the time axis.
3.5 waves correspond to 12.1 ms.
3.5 T = 12.1×10-3 s
Period T = 12.1×10-3
/ 3.5 = 0.0035 s
Frequency = 1 / T = 1 / 0.0035 = 290
Hz
Amplitude is the maximum
displacement. This can be obtained from the y-axis.
Amplitude
= 6.7 mm = 0.0067 m
