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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 the potential difference across a resister decreases to zero the current does what?
If the potential difference across a resistor decreases to zero, the current flowing through the resistor also becomes zero. This is due to Ohm's Law, which states that current (I) is directly proportional to voltage (V) across the resistor (I = V/R). With no voltage to drive the flow of charge, the current halts.
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.
What is effect of charged and uncharged capacitor at the resistance of it?
The effect of a charged capacitor on the resistance in a circuit is that it can lead to a temporary increase in current due to the initial discharge when connected to a resistor, while an uncharged capacitor behaves as an open circuit at the moment of connection. Over time, as the charged capacitor discharges, the current decreases exponentially until it reaches zero, effectively behaving like a resistor with a time-dependent resistance. In contrast, an uncharged capacitor will not allow current to flow until it starts charging, resulting in a different initial resistance characteristic. Overall, the capacitor's state (charged or uncharged) influences how it interacts with the resistance in the circuit.
How can the resistor be charged?
Resistors cannot be charged in the same way capacitors can, as they do not store electrical energy. Instead, resistors dissipate electrical energy as heat when current flows through them, based on Ohm's Law. When a voltage is applied across a resistor, it allows current to pass, and the resistor converts electrical energy into thermal energy according to its resistance value. Thus, while resistors are integral to circuits, they don't store charge.
If the potential difference across a resister decreases to zero the current does what?
If the potential difference across a resistor decreases to zero, the current flowing through the resistor also becomes zero. This is due to Ohm's Law, which states that current (I) is directly proportional to voltage (V) across the resistor (I = V/R). With no voltage to drive the flow of charge, the current halts.
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 is effect of charged and uncharged capacitor at the resistance of it?
The effect of a charged capacitor on the resistance in a circuit is that it can lead to a temporary increase in current due to the initial discharge when connected to a resistor, while an uncharged capacitor behaves as an open circuit at the moment of connection. Over time, as the charged capacitor discharges, the current decreases exponentially until it reaches zero, effectively behaving like a resistor with a time-dependent resistance. In contrast, an uncharged capacitor will not allow current to flow until it starts charging, resulting in a different initial resistance characteristic. Overall, the capacitor's state (charged or uncharged) influences how it interacts with the resistance in the circuit.
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.
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
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.
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.
