What are the correct conditions for Simple Harmonic Motion?

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Bolter
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Ok so here are a few multiple choice questions that I have been given to me and these are what my selected options turned out to be

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Screenshot 2020-02-28 at 09.25.45.png


Screenshot 2020-02-28 at 09.25.53.png


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Do they seem right?

I am rather confused on the wording of the first question?

Is it asking to state the conditions of SHM for it be in SHM?
I know that from the definition in my head SHM is a type of periodic motion or oscillation motion where the restoring force is directly proportional to the displacement and acts in the direction opposite to that of displacement

I know it must be option C as that matches in with the above definition I had given. Cannot be option B as it simply just says motion on a pendulum or spring but does not describe any features of SHM. But option A is describing Hooke's law and says nothing about the displacement or how acceleration is directly proportional to its displacement from equilibrium position?

Any help would be appreciated! Thanks
 
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Q1. I'd agree with you that( a) is almost the same as (c), but (c) is a bit more general, so better.

Q2. Again, I'd vote (c) as best answer. I don't like (b) because Θ is undefined and I think angular velocity needs to be about some point/axis , but (b) might be liked by people here because it is mathematical rather than words. I'll wait to see what they come up with.

Q3. correct, (b).

Q4. This one I find most difficult. My first reaction was to prefer (b) as the general definition of period, rather than (c) which seems to me to be a mathematical consequence of the definition of SHM.
On further reflection (& re-reading the question) (c), being a consequence of SHM is actually an advantage, when the question asks for a definition specifically of period for SHM. So I'll go for (c) despite my loathing of math's taking ownership of physics!
 
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Merlin3189 said:
Q1. I'd agree with you that( a) is almost the same as (c), but (c) is a bit more general, so better.

Q2. Again, I'd vote (c) as best answer. I don't like (b) because Θ is undefined and I think angular velocity needs to be about some point/axis , but (b) might be liked by people here because it is mathematical rather than words. I'll wait to see what they come up with.

Q3. correct, (b).

Q4. This one I find most difficult. My first reaction was to prefer (b) as the general definition of period, rather than (c) which seems to me to be a mathematical consequence of the definition of SHM.
On further reflection (& re-reading the question) (c), being a consequence of SHM is actually an advantage, when the question asks for a definition specifically of period for SHM. So I'll go for (c) despite my loathing of math's taking ownership of physics!

Ok thanks this has definitely cleared up a bit of misunderstanding that I had :) This was helpful