# What is the Voltage Across the Capacitor Immediately After Switch s1 is Closed

The initial voltage across the capacitor is zero after switch s1 is closed.

Before the switch closes, the capacitor’s charge Q is zero and its voltage across the capacitor is equal to zero **(V = Q/C = 0)**.

The capacitor’s charge has not had time to accumulate when the switch is closed, therefore the charge and voltage are still zero.

## After Switch S1 is Closed, What is the Voltage Across the Capacitor?

Zero is the obvious response. The capacitor has no charge just before the switch is closed. The voltage across the capacitor is thus zero. Additionally, the charge is not given adequate time to build up when the switch is closed.

### What Happens To A Capacitor When The Switch Is Opened

It is possible to charge a capacitor in an open circuit: Either the switch was opened while the capacitor was fully charged, or it may be completely depleted. Capacitors are also known to leak. In other words, they gradually lose their charge.

### What Occurs To The Capacitor When The Switch Is Closed

When the switch is first closed at time zero, the capacitor slowly charges through the resistor until the voltage across it equals the battery supply voltage.

### What Happens To The Voltage When A Capacitor Is Discharged

The capacitor does not lose its charge steadily as it discharges. The circuit’s starting conditions are **t = 0**, **I = 0**, and **q = Q** at the beginning of the discharging operation. The supply voltage is equal to the voltage across the capacitor’s plates, hence **VC = VS**.

### What Is The Voltage Across A Capacitor

So because charge (Q) is constant and equal, the capacitor’s value alone **V = Q /C** determines the voltage drop across the capacitor. Lower capacitance values will produce higher voltages, but bigger capacitance values will provide smaller voltage drops.

### What Happens To The Voltage When The Switch Is Closed

There is no voltage or current across the resistor or inductor prior to the switch being closed. Since it cannot change instantly, the current through the inductor is zero when the switch is initially closed. This indicates that the inductor behaves like an open circuit and that all of the voltage is applied across it.

### What Is The Capacitor’s Potential Difference Right After The Switch Closes

Immediately after the switch is flipped to the “charge” position, the capacitor. Since the capacitor is not charged, there is no potential difference. According to the loop rule, the potential difference across the resistor equals the emf of the battery because the closed switch has no potential difference.

### What Is The Current Through Immediately After The Switch Is Closed

This is caused by the circuit’s inductance and capacitance. Because of this, we state that unlike in a resistive circuit, the current in an RLC circuit will be zero as soon as the switch is closed.

### Why Is The Voltage 0 When The Switch Is Closed

A load should have a measurable resistance whereas a closed switch should have a resistance that is almost zero ohms. Because 0 ohms times whatever amount of current would still be 0 volts, using Ohm’s law to compute the anticipated voltage drop across a switch would result in a result of 0.

## Frequently Asked Questions

**What is the voltage across the inductor immediately after re-closing the switch?**

Since the current through the inductor cannot change rapidly when the switch is closed, the current is zero immediately afterward, **IR** is also zero, and V thus equals L dI/dt. dI/dt = V/L = 10V/10H = 1 A/s, thus.

## Conclusion

The charge across the capacitor immediately following the switch being closed is zero, which accounts for the initial voltage across the capacitor being zero. Additionally, the voltage across the capacitor is 0 according to the charge-voltage relationship.

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