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When a capaciter is charged through a resistor it shows maximum current at first and slowly it decreases why?
Because the voltage across the capacitor is initially zero, making the voltage across the resistor maximal. As the capacitor charges, the voltage across the resistor decreases, with an accompanying reduction in current. At maximum charge, the voltage across the resistor is zero, and thus there is no current.
The equation of a capacitor is ...
dv/dt = i/c
... meaning that the rate of change of voltage, in volts per second, is proportional to current, in amperes, and inversely proportional to capacitance, in farads.
Set this up into a series charging circuit, replacing the i term with (V-Vt) / R, solve the differential equation, and you get ...
Vt = VSource (1 - e-t/RC)
.... where Vt is voltage at some time t, and RC is the time constant, resistance times capacitance.
The is the DC state answer. AC circuits are a whole other issue, and require different analysis, though the fundamental equation remains the same.
What else can I help you with?
If a resistor decreases in value what will happen to the current through the resistor?
If the voltage applied across the resistor remains constant, then as the resistance of the resistor decreases, the current through it will increase. Consider Ohm's Law: E = IR In this formula, in order for 'E' to remain constant as 'R' decreases, 'I' must increase. Another form of Ohm's Law: I = E/R If 'E' remains constant, then the value of the fraction increases as its denominator 'R' decreases.
What happen to current when paralle resistor added?
For the individual resistor, the current is constant, regardless of any other resister that's attached to it in parallel. The current that results from all the resistors combined decreases as the resistance of one or more of the resistors increases.
How does load current vary with the load resistance?
Their relationship is only dependent on the voltage lost across that resistor; voltage equals resistance times current, so increasing the current for a given voltage will require a decrease in the resistance, and vice versa.
How do resistance behave in parallel circuit?
in a parallel circuit resistance decreases increasing the current.
A can be used to reduce the current in a circuit?
A resistor.
How does adding a resistor to an electric circuit affect the current flow?
Adding a resistor to an electric circuit reduces the current flow by impeding the flow of electrons. The resistor increases the resistance in the circuit, which in turn decreases the amount of current that can pass through.
If a resistor decreases in value what will happen to the current through the resistor?
If the voltage applied across the resistor remains constant, then as the resistance of the resistor decreases, the current through it will increase. Consider Ohm's Law: E = IR In this formula, in order for 'E' to remain constant as 'R' decreases, 'I' must increase. Another form of Ohm's Law: I = E/R If 'E' remains constant, then the value of the fraction increases as its denominator 'R' decreases.
How can a capacitor be charged without using a resistor?
A capacitor can be charged without using a resistor by connecting it directly to a power source, such as a battery, which provides a constant voltage. This allows the capacitor to store electrical energy without the need for a resistor to limit the flow of current.
What happen to current when paralle resistor added?
For the individual resistor, the current is constant, regardless of any other resister that's attached to it in parallel. The current that results from all the resistors combined decreases as the resistance of one or more of the resistors increases.
What happens to the ammeter reading if resistor is removed?
If the resistor is removed from the circuit, the total resistance in the circuit decreases. This causes the total current in the circuit to increase, which would result in an increase in the ammeter reading.
What will happen to the other resistor if the number of resistor decreases?
the voltage across that resistor will increase if it is in series with the other resistors. the current through that resistor will increase if it is in parallel with the other resistors.
How can a variable resistor be used to control the brightness of light?
A variable resistor can be connected in series with a light bulb in a circuit. By adjusting the resistance of the variable resistor, the current flowing through the circuit changes, affecting the brightness of the light bulb. Increasing the resistance decreases the current, resulting in lower brightness, while decreasing the resistance increases the current, leading to higher brightness.
How does current change through a resistor?
When an electric current flows through a resistor, the resistor resists the flow of the current, causing a decrease in the current. This decrease in current is proportional to the resistance of the resistor, as described by Ohm's Law.
What happens when you use a smaller resistor in place of larger one?
as we can deduce from its name, the resistor "resists" to the current (the movement of the electrons) so as the value of the resistor increases, the current flowing through it decreases. so when you use a smaller resistor, the current increases, however the tension between its poles decreases ( due to the voltage divider law). remember that the shortcircuit is due to the small value of the current , so we need always to have a resonable resistance on the circuit..... but not too high because joule losses we'll be more significant !! hope i've been clear :D
Does current flow through a resistor, or does it flow across a resistor?
Current flows through a resistor, not across it.
Why does fan goes slower when resistor is on?
A resistor used in a fan circuit reduces the voltage supplied to the fan motor, which decreases the speed of the fan. The resistance introduced by the resistor limits the current flow to the motor, resulting in a slower fan speed.
What happens in a series circuit if one of the resistors is replaced with a resistor having a lower resistance value?
In a series circuit, if one resistor is replaced with a resistor of lower resistance, the total resistance in the circuit decreases. This leads to an increase in the overall current flowing through the circuit.
