The energy from the source is converted into electrical energy electricity when the electrons flow through the conductor. If your using a battery a the source, it will be dead very quickly. Energy can not be created or destroyed, only converted from one form to another Law of Conservation of Energy.
Without anything else in the circuit to use that electrical energy it has to be release somehow. The electrical energy is converted into heat energy. The conductor and the battery will heat up and the heat energy will be radiated or conducted away. Because short circuits create a lot of heat they are a severe fire and burn hazard. To avoid these negative consequences many safety components have been developed to prevent short circuits.
Wires are covered with insulation low conductivity materials like plastic. Fuses, circuit breakers, and 'ground fault indicators' are all used to stop the flow of electricity if a short circuit is detected. A complete circuit has a source and a path, but also has a component called a Load that uses the electrical energy. Loads can convert electrical energy into mechanical, thermal, or electromagnetic energy.
For example, you could create a circuit that connects each side of a battery to a light bulb with wires. The electricity flows from the battery, through the light bulb producing light and then back to the battery.
This is like the circuit you might find in a flashlight. The electrical energy is used by the light bulb to produce light. Because the wire a conductor still has some resistance, some of the energy will still be converted into heat and the light bulb most likely produces some heat infrared radiation in addition to the visible light. The efficiency of a circuit tells you how much of the energy is being uses and how much is wasted. Florescent light bulbs are more efficient than incandescent light bulbs, but modern LED light bulbs are more efficient than both of them.
Incandescent light bulbs produce the most heat and LED light bulbs produce the least amount of heat. Write your answer Related questions. What advantage do parallel circuits have over series circuits? What is the difference between parallel and series?
Why do you use series and parallel circuits? Made up of series and parallel circuits? How are parallel circuits different from series circuits? Series circuits and parallel circuits how do they differ? What is the nature of electric circuits for domestic use? Differences between series circuits and parallel circuits? How are electric circuits wired? What is the name of the circuit that is neither parallel nor series? What are the types of circuits? What is meant by series and parallel circuits?
How are switches used in electrical circuits to control parallel loads connected? What are the type of circuits used in wiring installation? What are the three basic different types of electrical circuits? Are household circuits normally wired in series or in parallel? Do bedrooms have parallel or series circuits? What are the differences between parallel circuit and series circuit?
Do you have series or parallel circuits in your home? What are the advantages of Norton's theorem? The electrical wiring in your house uses what type of circuitry? Is a series circuit better than a parallel circuit? What object is made up of series and parallel circuits? Study Guides. Trending Questions. Julia invested at an annual interest rate of 5 percent. From last year to this year there has been a 4 percent inflation rate. After a year the purchasing power of her investment.?
A boat can travel from its dock to a town downriver with a 7 mph current in 10 hours. The return trip against the same current takes 15 hours. What is the speed of the boat in still water? We begin by considering the effective resistance when components are connected in series and in parallel. The link between voltage and energy transfers leads to ideas about energy and power.
Conservation laws charge and energy lead directly to Kirchhoff's laws and these in turn provide a method for solving a large range of circuit problems, including potential dividers. Teaching Guidance for A joulemeter will be useful when discussing energy and power in electric circuits. It is worth practising with it before using it in any demonstration. Find a selection of ready-made potential dividers also known as potentiometers. Look for the three connections, characteristic of a potential divider.
Take the back off a rotary potentiometer to see the resistive material, and the wiper. Series and parallel circuits. By this stage, students should be able to distinguish between charge, current and voltage; they should understand the definition of resistance, and be competent in handling equations involving these four quantities. However some pupils will probably still be unwittingly harbouring some misconceptions, for example in the area of potential differences in parallel circuits, so be prepared to test, rather than to assume knowledge.
Topics remaining in basic electricity include EMF and internal resistance. Then students will be equipped to understand many different circuits, alternating current, etc. Adding resistors in series increases the effective resistance Adding resistors in parallel decreases the effective resistance. Ask students to recall the equation which defines resistance. Connect 1, 2 and then 3 lamps in series across a supply constant pd showing them the reduction in current at the same pd The ratio V I has increased: adding resistors in series increases overall resistance.
You may wish to calculate the resistance each time but beware that, since the temperature of the lamps will be different at different currents you are unlikely to get a simple ratio of resistances. Repeat the experiment but this time add lamps in parallel.
The current increases and the effective load resistance decreases. Episode Connecting lamps in parallel and in series Word, 34 KB. Now tackle the theory.
You are trying to find the single resistor R total which will have the same resistance as two or more resistors R 1 , R 2 etc in series. Derive the equations for series and parallel resistance combinations. The starting points are:. Beware that the parallel formula is usually quoted as 1 R total so they still have to take the reciprocal to get the value of R total.
It is unusual at A-level for questions to involve more than two resistors in parallel so it is worth pointing out that the parallel formula for two resistors can be rearranged to give:. It is also worth pointing out that when n resistors of the same value R are connected in parallel the result is an effective resistance R n.
Link this with an n-fold multiplication of current. Beware that, even at this level, some students will argue that current always takes the path of least resistance. Be prepared to discuss what happens in the extreme case when a component is shorted out by a piece of wire in parallel.
Point out that a small fraction of the overall current still continues to flow through the component. This case will re-emerge later in potential dividers in. You may need to mention conductance at this point.
In a parallel combination, conductances add. Work through examples for two resistors with convenient resistances, e. Allow students to perform the calculation for themselves and help out any students who have problems using the reciprocal key on their calculators. Emphasize that, for resistors in series, the total is always greater than the individual resistances; in parallel, it is less than any of the individual resistances.
Students can measure resistances of different combinations of resistors using an ohm-meter, and compare their answers with calculated values. You may wish to review the use of the ohm-meter prior to this activity.
The range on an ohm-meter can be confusing. Obviously this varies from device to device — make sure they are familiar and competent with the meters you intend them to use; otherwise the points about series and parallel circuits will be lost. Episode Resistors in series and in parallel Word, 36 KB. Episode Circuit resistance Word, 51 KB.
Episode Combining resistances Word, 31 KB. In this episode, students find that the energy transferred by an electrical component depends on the potential difference across it, the current through it and the time for which it operates. Start by reviewing the effect of increasing the voltage across a filament lamp. The current through the lamp increases and the lamp gets brighter. Episode Energy transferred by a lamp Word, 28 KB.
Remind your students that the pd is defined as the energy transferred per coulomb and that the current is the number of coulombs per second. If the lamp is connected to a joulemeter you can show that the number of joules transferred increases with time and that the rate increases when voltage and current increase. This should lead to the word equation:.
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