a) If there is no resistor in the circuit ( as in , if you completely remove the resistor) , then there will be no current flowing in the circuit. However, there will be a voltage at the 2 terminal points where the removed resistor used to be.
What happens if you dont use a resistor?
The resistor limits the current flow. There would be nothing to limit the current and the general answer is that the LED would be destroyed.
Why do we need resistors in circuits?
In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses.Resistors are also implemented within integrated circuits.
What is a circuit with no resistance?
A short circuit is an electric circuit offering little or no resistance to the flow of current. Short circuits are dangerous with high voltage power sources because the high currents encountered can cause large amounts of heat energy to be released.
Do I need a resistor?
They may be small and often built-in to other components, but resistors are essential to almost every electrical circuit. These hidden resistors are essential because they control the flow of the electrical current to sensitive components, and they protect components from voltage spikes.
Where does the resistor go in an LED circuit?
Since this resistor is only being used to limit current through the circuit, it can actually be located on either side of the LED. Placing the resistor on the positive (anode) side of the resistor will have no differing effects from placing the resistor on the negative (cathode) side of the LED.
What is the purpose of a resistor What function does it perform?
The purpose of a resistor is to provide a precise amount of electrical resistance in a circuit.
Do resistors reduce voltage or current?
A resistor has the ability to reduce voltage and current when used in a circuit. The main function of a resistor is to limit current flow. Ohm’s law tells us that an increase in a resistors value will see a decrease in current. To reduce voltage, resistors are set up in a configuration known as ‘voltage divider’.
What happens if resistance is too low?
If resistance is too low, current will be high at any voltage. If resistance is too high, current will be low if voltage is okay. NOTE: When the voltage stays the same, such as in an Automotive Circuit… current goes up as resistance goes down, and current goes down as resistance goes up.
Can resistors lose resistance?
If you’re running the resistor at or above its maximum rated power, it may gradually degrade over time, the actual resistance value drifting off spec until it either fails completely or gets far enough off its normal value that the circuit it is part of stops working.
How do resistors affect voltage?
The larger the resistor, the more energy used by that resistor, and the bigger the voltage drop across that resistor. Ohm’s Law can be used to verify voltage drop. In a DC circuit, voltage equals current multiplied by resistance. V = I R.
What happens if you don’t use a resistor with an LED?
When hooking up an LED, you are always supposed to use a current-limiting resistor to protect the LED from the full voltage. If you hook the LED up directly to the 5 volts without a resistor, the LED will be over-driven, it will be very bright for a while, and then it will burn out.
How is a resistor connected in a circuit?
Resistors are said to be connected in “Series”, when they are daisy chained together in a single line. Since all the current flowing through the first resistor has no other way to go it must also pass through the second resistor and the third and so on.
Does each LED need a resistor?
For individual single LEDs, a resistor for each is simple and always works. Some LED driver ICs do away with the need for that by having constant current driver outputs, so no resistor is needed there.
Why do you think a resistor can resist the flow of current?
This flow of electrons is called an electrical current. The electrons do not flow freely through the circuit as the material they move through creates a restriction to the electron flow. This restriction is called resistance.
Why are resistor values not exact?
It’s difficult to make a resistor to an exact value (and in most circuits it is not critical anyway). Resistances are given with a certain accuracy or tolerance. This is expressed as being plus or minus so much of a percentage.
Do resistors have positive and negative?
Resistors don’t have positive or negative terminal. However, when current flows through a resistor then the voltage drop across the resistor do have a polarity. Polarity of voltage drop depends upon the direction of current as shown in figure below.
How does a resistor affect an electrical circuit?
Resistor reduces the flow rate of electrons . That results in potential difference across it. Even a conductor has certain resistance across its given length. Flow of electrons takes place under the effect of electric field.
Does a resistor reduce power consumption?
Resistors consume power and dissipate that power by converting it to heat (and sometimes light). You can think of a piece of metal as a resistor.
What happens inside a resistor?
A resistor works by restricting the flow of current, it can do this in one of three ways: firstly, by using a less conductive material, secondly by making the conductive material thinner and finally by making the conductive material longer.
What causes a resistor to burn?
By applying too high a voltage to a resistor, the resistor will draw too much current. This causes excessive power to be dissipated in the resistor which makes it go up in flames and a cloud of smoke as this video shows.
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