Below are our answers for the mentioned worksheet:
1.1 What are waves?
a) What is the source of wave?
Oscillation or vibration. Wave is only created when the rope is vibrated.
b)What is the medium through which the wave moves?
String molecules. The string molecules vibrates as energy is being transferred onto it.
c) Does wave transfer matter?
No. The molecules moves in a up-down oscillating motion, but the wave moves in a left to right horizontal motion. Thus, the wave is not transferring matter as the direction of their motions are different.
d) Does wave transfer energy?
Yes. The energy from one molecule is transferred to another molecule, resulting in similar oscillatory motion and results in a wave.
1.2 Wave terms
Amplitude (Symbol, A, Unit, m) - Maximum displacement from the rest position
Wavelength (Symbol λ, Unit, m) - Distance between any two identical points on successive waves
Period (Symbol T, Unit, s) - Time taken to produce one complete wave
Frequency - Number of complete waves produced per second.
Relationship between Period and Frequency
T = 1/f
f = 1/T
1.3 Graphical Representation of Waves
a) Amplitude of waves is 0.4m
b) Wavelength of wave is 1 and 2/3 m
c) Period of wave is 1.5s
d) Frequency of wave is 2/3s
1.4 Wave speed
Speed = Distance/Time
= 1 and 2/3 m / 1.5 s
= 1.11 (3 s.f.)
a) Speed = Distance/Time
= 90 cm / 1.69 s = 53 and 43/169 cm/s
b) To change the speed of the wave pulse of the same width, we can either increase the tension of the medium or increase the linear mass density.