Anythin

Oscillations MCQ

Simple Harmonic Motion

Question H1: Why study this stuff?
Simple harmonic motion (SHM) is a technical term used to describe a certain kind of idealised oscillation. Practically all the oscillations that one can see directly in the natural world are much more complicated than SHM. Why then do physicists make such a big deal out of studying SHM?
A: It is the only kind of oscillation that can be described mathematically.
B*: Any real oscillation can be analysed as a superposition (sum or integral) of SHMs with different frequencies.
C: Physics is concerned mainly with the unnatural world.
D: Students are too stupid to appreciate the real world.
E: It is good torture for students.

Feedback:
You should be able to get answer B because it is meant to look like the only sensible statement on the list. However the question itself is not so silly. If you understand SHM you have progressed a long way towards understanding all kinds of oscillations. This is one of the typical things about physics that make physicists think that it is an easy subject; if you understand simple idealised things like SHM then you understand a helluva lot.

Question H2:
Simple harmonic motion (SHM) is a technical term used to describe a certain kind of idealised oscillation.
    A simple harmonic oscillation has
A*: fixed frequency and fixed amplitude.
B: fixed frequency and variable amplitude.
C: variable frequency and fixed amplitude.
D: variable frequency and variable amplitude.
?: Don't know.

Feedback:
In the idealised world where one can talk about a simple harmonic motion, the SHM goes on repeating itself exactly forever. Since it takes only one value of frequency to specify the motion, that frequency must be unchanged. Also, in the idealised world, since the motion repeats itself exactly the amplitude must also be constant. Mathematically SHM can be described by a sine function multiplied by a constant (the amplitude). The sine function is one of...