```Lesson 21 questions – Oscillations
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ALL
1
Estimate the time periods of each of the following motions and hence calculate
(to 1 s.f.) their frequencies.
a)
a child on a playground swing
period = ……1……….s (1)
frequency = ……1……… Hz (1)
b)
a baby rocked in its mother’s arms
c)
period = ……0.5……….s (1)
frequency = ……2.0……… Hz (1)
period = ……0.67……….s (1)
frequency = ……1.5……… Hz (1)
2
The pendulum bob of a grandfather clock swings through an arc of length
196mm from end to end. The period of the swing is 2.00 s.
a)
Explain what is meant by the period of the swing.
…………The time
for 1 full oscillation……………………………………………………………..
…………………………………………………………………………………………..
…………………………………………………………………………………………..
……………………………………………………………………………………… (2)
b)
What is the amplitude of the swing?
Amplitude = …0.098………… m (1)
c)
What is the frequency of the bob?
Frequency = …0.5………… Unit ……Hz…… (2)
3
What is (i) the frequency (ii) the period of:
a)
the rise and fall of the sea
i)……0.000022……………. Unit …Hz……. (2)
ii)………45…………. Unit …ks…… (2)
b)
the beat of a heart
c)
i)………1.17…………. Unit …Hz……. (2)
ii)……0.85……………. Unit …s…… (2)
piano strings which oscillate when middle C is played
i)………256…………. Unit …Hz……. (2)
ii)……3.9……………. Unit …ms…… (2)
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