Basic electricity study guide pdf download

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Books Video icon An illustration of two cells of a film strip. The open will be isolated to that branch and current will continue to the other lights in the strand, Joy…to… the…World! R1 represents the resistance value of the speaker and R2 shows the resistance value of the LEDs. What is the voltage supplied to the LEDs and to the speaker? First, we need to find the current in the loop once the belly is pressed and switch 1 S1 closes. The supply offers 5 amps of current but the circuit will only use what is demanded by the loads.

This circuit is known as a voltage divider circuit. The supply voltage was divided among the loads in proportion to the resistance each load carries. This law states that the algebraic sum of the voltages in a closed loop is always equal to zero. If we only knew the supply potential and the voltage drop of R1, we could use KVL to find the other voltage drop. With KVL you have to follow the current path and use the polarities of the components shown.

If current path is unknown you have to assume one. We will use the positive to negative clockwise path. KVL really comes in handy when there are multiple supplies in a loop or multiple loops. As mentioned previously, with parallel circuits the voltage across each branch will be equal to the supply voltage. First we need to find the total resistance in the circuit. In series circuits we would just add all of the resistance values together. In parallel, you have to add the reciprocals of all the resistance values together and then reciprocate back.

High fives all around! One quick note, current will always try to take the path of least resistance. I was taught to think that current flows much the same as water. If you have two channels in a river and one is partially blocked by logs, then most of the water will flow through the clear channel.

Same is true with current. In a parallel circuit, the branch with the least amount of blockage or resistance will receive the majority of the current. In our example both channels are partially blocked but the one that is most clear R2 will receive the most current. Pop Quiz, what if R2 was to short out? Well, in a short there is no resistance, so all of the current would flow though that branch.

The wire could overheat causing the worm to lose its glow and quite possibly everything else. Time for a little recap: in series circuits, current is constant and voltage varies but in parallel circuits voltage is constant and current varies.

AC and BD as shown in fig 1a. AB and CD as shown in fig 1b. In Fig 2, a lamp is controlled from three different places by using two, 2-way switches and one intermediate switch. A lamp is controlled from six different places by using two, 2-way and four intermediate switches. Key Point: You can control a lamp from many different places by adding more intermediate switches.

Electrical and Electronic Switches: The Above discussed switches are Mechanical switches and they are user manually operated. Now, we are going to discuss Electrical switches, which are faster in response than mechanical switches and can be switched automatically by an electronic circuit like microcontroller or microprocessor. They can also be categories on the basis of current and voltage rating like mechanical switches.

Transistor:- Transistor can be used in different mode of operation but we are going to discuss the transistor as a switch. If we apply a large amount of current at the base of the transistor keeping in mind the maximum allowed current for the this type of transistor then we can run this transistor in deep saturation mode 2.

Mosfets:- Mosfet can also be used for switching purpose at high frequencies. They can operate at Mega hertz frequencies. Mostly, Mosfets used for PWM pulse width modulation. Mosfets have three terminals.

Relays:- A Relay is an electromechanical device, which consists of an electromagnet. When a current is flowing through the coil, it becomes an electromagnet and this electromagnet can be used for switching purposes.

Their contacts can fall into any category, e. When they do work moving charges against the electric force, some of this work is already converted to thermal energy in the battery. The amount of energy lost to thermal energy in the battery is Ir, where I is the current flowing in the circuit and r is the internal resistance of the battery.

The voltage across the battery terminals therefore drops from the nominal value V to V - Ir when a current is flowing in the circuit. In a circuit diagram we represent the internal resistance of the battery by a resistor r connected in series with the emf.

A voltmeter is a device used to measure voltages, while an ammeter measures currents. Meters are either analog or digital devices. Analog meters show the output on a scale with a needle, while digital devices produce a digital readout. Analog voltmeters and ammeters are both based on a device called a galvanometer. Digital voltmeters and ammeters generally determine the voltage drop across a known resistor and then convert the result to a digital value for display.

Voltmeters Resistors in parallel have the same voltage across them. If you want to measure the voltage across a circuit element, such as a resistor, you place the voltmeter in parallel with the resistor.

The voltmeter is shown in a circuit diagram as a V in a circle, and it acts as another resistor. To prevent the voltmeter from changing the current in the circuit and therefore the voltage across the resistor , The voltmeter must have a resistance much larger than that of the resistor. If the resistance of the voltmeter is large, only a negligible current flows through the meter. An ammeter must be placed in series with a resistor to measure the current through the resistor.

On a circuit diagram, an ammeter is shown as an A in a circle. The ammeter acts as a resistor. To prevent the ammeter from changing the current in the circuit, The ammeter must have a very small resistance compared to the resistance R of the circuit. So now I am going to provide you some connections as a word and then you will try to connect about these connections. Already you are given answer of question one so they are 50 questions.

Connect one bulb by one switch AC? Connect two bulbs by two switches as a parallel AC? Connect three bulbs by three switches as a parallel AC? Connect one switch and three bulbs by series connection AC? Connect one switch with two bulbs by parallel AC? Connect three bulbs with one switch by parallel AC? Connect two switches with one bulb and socket by parallel AC?

Connect two bulbs with one switch by series connection AC? Connect one bulb with one switch, two parallel bulbs with one switch two series bulbs with one switch and 5 amp two pin socket with one switch AC? Connect two series and three parallel bulbs connection by one switch if one of series bulbs out from the batten holder parallel bulbs will off AC? Connect two series and three parallel bulbs with one switch if one series bulb out from batten holder the other parallel bulbs will not off AC?

Connect one ceiling fan with one switch AC? Connect one bulb with one switch, three series and three parallel bulbs with one switch, two ceiling fan with two switch, one two pin socket with one switch AC? Connect one bulb with one switch, two ceiling fan with one switch, 2 two pin socket with one switches AC? Connect one calling bell controlled with one push switch AC?

Connect one calling bell controlled with two push switch by series AC? Connect one calling bell controlled with two push switch by parallel and difference watt of bulbs AC? Connect one calling bell controlled with three push switch by parallel and difference watt of bulbs AC? Connect one calling bell controlled with four push switch by parallel and difference watt of bulbs AC?

Connect one bulb with one switch, two parallel bulbs with one switch, three series bulbs with one switch, two ceiling fan with one switch, two sockets pin with one switch and one calling bell with one switch AC? Connect one gang one way switch with two bulbs of parallel AC? Connect two gangs one way switch with two bulbs of parallel AC?

Connect three gangs one way switch with three bulbs of parallel AC? Connect four gangs one way switch with four bulbs of parallel AC? Connect five gangs one way switch with five bulbs of parallel AC? Connect one gang one way switch with two pin socket AC? Connect one gang one way switch with one ceiling fan AC? Connect one bulb with two way switch by series connection AC?

Connect one bulb controlled from three places by using two way and intermediate switch AC? Connect one bulb controlled from four places by using two way and two intermediate switch AC? Connect two bulbs with one switch by parallel and two bulbs controlled from two places by parallel AC? Connect 15 Amp socket with 15 Amp switch and circuit breaker AC? Connect one six pin combined with circuit breaker AC? Connect one six pin combined and indicator lamp with circuit breaker AC?

Connect one bulb with one switch, one ceiling fan with one switch, one calling bell with one switch, one templar socket 5 Amp with one switch, one templar socket 15 Amp with templar switch to operate by water pumps, one six pin combined with circuit breaker to operate one fridge AC?

Connect one tube light with one switch AC? Connect one tube light with one switch and one bed switch AC? Connect one bulb that will difference bright once high and once low by using capacitor AC?

Connect 15 Amp socket with 15 Amp switch and with two separate circuit breaker AC? Connect to test lamp with switch series circuit board or make series circuit board by one switch AC? Connect series with parallel circuit board by one switch AC? Connect series lamp for working two phase line AC? Connect two bulbs with two switches separately, two ceiling fan with two switches, two series bulbs with one switch, three parallel bulbs with one switch, one bulb controlled from two places, two difference bright of light with one switch, one tube light with bed switch by one switch, one calling bell will ring from two places, two 5 Amp socket with one switch, one six pin combined socket to operate refrigeration, 15 Amp socket connection to operate water pump AC?

Connect one voltmeter by single phase line by using always parallel connection AC? Connect one Ammeter by single phase line by using always series connection AC? Connect one Voltmeter and one Ammeter connection by in single phase line AC?

Connect three Voltmeter by three phase line watt AC? Connect three Voltmeter by three phases with one line watt AC? Connect three Voltmeter and three Ammeter connections by in three phases line watt AC? Connect two bulbs with one switch separately, one bulb two difference bright of lighting, two series and two parallel bulbs controlled from one place, one ceiling fan with one 2 pin socket, one tube light with one switch, one calling bell controlled from two places to operate one fridge and one water pump connect by power socket with all types of devices AC?

Piano fuse 2. Piano switch 3. Red wire phase 4. Batten holder 5. Bulb 6.