A loudspeaker cone is driven by a signal generator (oscillator) - AQA - A-Level Physics - Question 6 - 2019 - Paper 1
Question 6
A loudspeaker cone is driven by a signal generator (oscillator). Figure 8 shows the variation of displacement with time for a point P at the centre of the cone. P is... show full transcript
Worked Solution & Example Answer:A loudspeaker cone is driven by a signal generator (oscillator) - AQA - A-Level Physics - Question 6 - 2019 - Paper 1
Step 1
State the time, in milliseconds, when P is moving at its maximum positive velocity.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The maximum positive velocity occurs when the displacement is at zero, moving from positive to negative. Referring to the graph, this occurs at 1.5 ms.
Step 2
Calculate the maximum acceleration of P.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To find the maximum acceleration, we use the formula:
amax=A⋅(2πf)2
From the graph, the amplitude (A) is 4.2 mm (or 4.2×10−3 m), and the period (T) is 2.0 ms (or 2.0×10−3 s). We first calculate the frequency (f):
f=T1=2.0×10−31=500Hz
Next, substituting the values:
amax=4.2×10−3⋅(2π(500))2≈4.1×10m/s2
Step 3
The loudspeaker creates variations in pressure and produces a sound wave in the air around it.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The type of wave produced is a longitudinal wave. In this type of wave, the particles of the medium (air) oscillate parallel to the direction of energy transfer. As the loudspeaker cone moves, it compresses and rarefies the air particles, causing sound to travel through the medium.
