# Tag Info

1

The component that ensures the current is zero just after the switch is closed is the inductor. Inductors do not like changes in current, since a change in current means the magnetic field linking the inductor is changing and this generates a back emf that opposes the change. If you replace the inductor with a piece of wire you would have an RC circuit and ...

1

Setting up the differential equation $$L \frac {dI}{dt} + RI + \frac {Q}{C} = V$$ will not necessarily answer your question, "What and how can I conclude about the current in this circuit just after switch is closed." If you look at the methods of solving the differential equation somewhere on the way to the solution initial conditions are needed, one of ...

3

So, we have series LCR circuit. $V$ is a constant voltage source. $L$, $C$, and $R$ represents the inductance, capacitance and resistance in the circuit respectively. A current $I$ flows through the circuit. Now, the current through each component is the same. So, the potential difference between each component added up together gives the emf $V$. ...

3

From Kirchhoff's second law, the sum of all the voltages around a loop is equal to zero. That is, the sum of the voltages across the three elements of your circuit, R, L and C, must be equal to the time varying voltage from the source: $$V_R+V_L+V_C = V(t)$$ As $V_R=RI$, $V_L=L\frac{dI}{dt}$ and $V_C=\frac{Q}{C}$, we get your equation, which is correct: ...

0

I guess the answer is simple. If the system should maintain a certain current and there appears an electromotive force, that would reduce the current according to the induced negative voltage. Only if the voltage is compensated by the reverse voltage from the power supply will the current stay constant.

1

Yes - this is done regularly with levitation induction heating and here

1

Is it possible to levitate something inside a solenoid Why not? One can levitate a small frog whose mass is less.The skin of most animals are diamagnetic in nature so it repels the external field.One can adjust the mass of the diamagnetic material such that it is repelled by an equal amount of force which increases till the centre of the non ideal ...

1

Schrodinger's Cat explains well why only part of the impendance is taken. Why are they considering a phase difference of $\phi$ ... Also, why are they taking modulus of Z Here's an algebraic explanation: For the RLC circuit, we can write the total impedance in a general form, $$Z_T=R + j Z_r,$$ where $Z_r$ is the total reactive impedance of the $L$'s ...

2

Why are they considering a phase difference of $\phi$? Your calculations are not totally correct. The voltages across different impedants $V_C,V_R,V_L$ have a phase relationship between them and hence the different impedances $Z_C,Z_R,Z_L$ are not directly linearly related as you have done. Consider the following phasor diagram: I hope it is clear ...

1

I'm assuming that you are asking this question in context of an L-C circuit. The reasonant frequency of an L-C circuit is given by the formula $$f = \frac{1}{2\pi}\sqrt{\frac{L}{C}}$$ where L is the inductance of the inductor and C is the capacitance of the capacitor. Hence if any of these two values are changed the reasonant frequency of the circuit will ...

Top 50 recent answers are included