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## Homework Statement

In the

**tuned**circuit below, what will happen to the reading of the ammeter when:

a) source frequency increases. The voltage is constant

b) the capacitance increases. The voltage and source frequency are constant

c) The voltage increases. Source frequency is constant.

## Homework Equations

ƒ =1/(2π√LC) Where: C is the capacitance and L is the inductance.

I= V/Z Where: V is the voltage and Z is the impedance.

Xc=1/ωC

Xl=ωL

Z=√R²+(Xl-Xc)²

## The Attempt at a Solution

Here is my solution:

a) the ammeter reading decreses.

**Explanation**: when source frequency varies the circuit is no longer in resonance so the impedance increases,

Z=√R²+ (Xl-Xc)²

b) the ammeter reading decreases.

**Explanation:**when the capacitance C increases, Xc decrease, then (Xl-Xc) increses, hence the impedance increases because:

Z= √R²+(Xl-Xc)²

c) the ammeter reading increases.

**Explanation:**since source frequency is constant, the circuit is still in resonance. So, increasing in voltage will increase the current becuase the impedance of the circuit will not change.

Am I correct?