- #1
Mayan Fung
- 131
- 14
I need to introduce Simple Harmonic Motion to a group of high school students studying physics. They don't know anything about differential equation except the method of separation of variables. Also, they have limited knowledge on complex numbers like eiωt. However, I don't want to just give the solution and let they check that the solution fits the equation. Is there any method that can clearly show the logic?
I have an idea here.
$$ \frac {d^2x}{dt^2} = -ω^2 x $$
$$ v\frac {dv}{dx} = -ω^2 x \text{ } (v = \frac{dx}{dt}) $$
then I can get sth relating dx/dt and x, thus finding x(t)
If I did the math correctly, it should be
$$ x(t) = Asin(ωt+φ) $$
I would think this is a logical way that the students would be convinced with the result.
However, it still looks a bit clumsy and I have never seen anyone do this before. Is there any simpler way to solve this equation logically? Thanks!
I have an idea here.
$$ \frac {d^2x}{dt^2} = -ω^2 x $$
$$ v\frac {dv}{dx} = -ω^2 x \text{ } (v = \frac{dx}{dt}) $$
then I can get sth relating dx/dt and x, thus finding x(t)
If I did the math correctly, it should be
$$ x(t) = Asin(ωt+φ) $$
I would think this is a logical way that the students would be convinced with the result.
However, it still looks a bit clumsy and I have never seen anyone do this before. Is there any simpler way to solve this equation logically? Thanks!