SHM and Total Energy Equations for Solving Homework Problems

[Cici2017]

Homework Statement

Homework Equations

The Attempt at a Solution

KE=1/2mω²x²
doesn't this mean is it proportional to all A.B.C&D?
Thank you!

 

[mjc123]

Well, for a start it can't be proportional to both the time period and the frequency. If it's proportional to one it must be inversely proportional to the other. ("Proportional" does not mean simply "depends on" or "related to"; it indicates a specific kind of dependence.)
What does your equation tell you about the dependence on the amplitude?
Do you know a formula for ω (or alternatively for T, the time period)? If you plug this into your equation, what does it tell you about the dependency on mass and frequency?

 

[Cici2017]

Well, for a start it can't be proportional to both the time period and the frequency. If it's proportional to one it must be inversely proportional to the other. ("Proportional" does not mean simply "depends on" or "related to"; it indicates a specific kind of dependence.)
What does your equation tell you about the dependence on the amplitude?
Do you know a formula for ω (or alternatively for T, the time period)? If you plug this into your equation, what does it tell you about the dependency on mass and frequency?

1/2m(2πf)²x²
so proportional to mass and proportional to frequency squared and amplitude squared?

 

[mjc123]

Yes, proportional to the amplitude squared, so A is wrong.
As to frequency, I was thinking of another equation. What physically determines the frequency of an oscillating system? Specifically, in terms of mass and force constant?

 

[Cici2017]

Yes, proportional to the amplitude squared, so A is wrong.
As to frequency, I was thinking of another equation. What physically determines the frequency of an oscillating system? Specifically, in terms of mass and force constant?

ummm... I think we haven't covered this in class yet.

 

[mjc123]

Then why have you been given the question?

 

[Cici2017]

Then why have you been given the question?

I'm not sure. May be we have. What equation is it?

 

[mjc123]

Have you come across the equation ω = √(k/m), or its equivalent T = 2π√(m/k) ?

 

[mjc123]

Or think about it another way: What is the maximum potential energy?