Describe the relationship between the voltage across and inductor and the voltage across a capacitor in an AC circuit. Explain how the relative sizes of these voltages will vary as the frequency of the AC supply is increased.
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Zaloum's Physics Discussion 
As the frequency of the supply voltage increases the capacitor will have less and less of an effect, while the inductor will have a greater effect.
Formula’s:
The formula for a capacitor’s reactance is Xc = 1/wC
while the formula for the reactance of an inductor is XL= wL
and the formula for the voltage of a component is V=XL
As we can see from the equations an inductor’s reactance (and therefore voltage) increases as the frequency increases. While a capacitor’s reactance and voltage decrease with a frequency increase.
As the frequency of the supply voltage increases the capacitor will have less and less of an effect, while the inductor will have a greater effect.
Formula’s:
The formula for a capacitor’s reactance is Xc = 1/wC
while the formula for the reactance of an inductor is XL= wL
and the formula for the voltage of a component is V=XL
As we can see from the equations an inductor’s reactance (and therefore voltage) increases as the frequency increases. While a capacitor’s reactance and voltage decrease with a frequency increase.
Hello Eli, living in your car. You have the beginnings of a good answer and you have the idea, just need to address the question more directly:
First talk phase, Vc and VL are 180 degrees out of phase and so the two Vc and VL voltages partially cancel in an AC circuit (or completely cancel at resonance). Then…
As frequency is increased, the voltage across the inductor is increased (as the reactance of the inductor increases with frequency: XL=wL)
At the same time, the voltage across the capacitor will decrease as the reactance of the capacitor decreases when frequency is increased (Xc=1/wC)