by Ron Kurtus
You can read them to further your understanding of the subject.
|AC||AC and DC current and resistance||Afghanistan|
|AC Transformers||How can I reduce my electrical costs?||UK|
|AC||Difference between right-hand rule and other names||India|
|Generating Electricity||Can electricity be generated in home?||India|
|AC Transformers||Specific voltage conversion with wire size||USA|
|DC||Want to use lightning as a power source||India|
|DC||Is the direction of the current opposite during charging?||USA|
|DC Circuits||Resistance when wire is bent||Pakistan|
|AC Transformers||Who was the father of transformer?||India|
|Electrical Charges||Evaluate vectors||Nigeria|
AC and DC current and resistance
November 14, 2011
I have question regarding AC and Dc current and resistance:
If we have the same voltage and resistance in AC and DC circuit, then why we have different current in different circuit.
Abdul Sami - Afghanistan
Assuming it is a simple circuit with a power supply and a resistor, there are a number of factors involved.
If the AC voltage is peak voltage, Ohm's Law or V = IR does not hold up. Since the AC voltage is a sine wave, the voltage must be RMS (root-mean-square), which is 0.707 of the peak voltage. In this case, AC and DC current should be the same.
If the AC circuit includes a capacitor and/or an inductor, the law does not hold.
How can I reduce my electrical costs?
Topic: AC Transformers
October 31, 2011
this is an informative site. thankyou. I have been toying with an idea to cut domestic electrical costs. In a nutshell, and as a crude guide, i was wondering how energy consumption, from one 230v outlet, would conclude, if i connected a 110v transformer with a 230v intake into a household ssocket. then attach a larger 110v transformerthat converts back to 230v, with several output connections. theory being... create 4 or more 230 outlets from one 230 consumption point, via a drop down 110 transformer. your genius is appreciated
Neville - UK
Electrical costs are usually measured in kilowatt-hours, which are thousands of watts per hour. (See Electrical Power).
AC transformers use power to convert the voltages. Putting them into your home system would actually increase your wattage use. Also realize that many devices are made for 230V and will not run effectively on 110V.
Some ways to cut domestic electrical costs are to start converting away from incandescent light bulb to the new low wattage bulbs, disconnect "always on" adapters from various devices. If an adapter feels warm, it is using electricity even if the device is off. Many remote control television sets draw energy all the time, so that they can turn on instantly. Also, many older electrical devices are very inefficient.
Also, simply being conscious of excess electrical use--such as leaving the lights on when no one is home--can greatly decrease your costs.
Best wishes in lowering your electrical costs.
Difference between right-hand rule and other names
October 31, 2011
Is the 'right hand thumb rule' and the 'right hand rule' same.
I am in a great confusion. Wikipedia says so. But the NCERT textbook give their definitions distinctly and without any relation.
Are they same or different? Basically they are different as they are rules for totally different things. But that might not prove that they have no internal relations. Please I need help.
The talk page of Right-hand rule in wikpedia contains discussion about the same things that may help you get my question more clarified.
Thank you. I love school for champions very much.
I searched the web many times but failed to get a clear answer. Also you may create an article about Right hand thumb rule so that those people like me can find the right answer. Also it will serve as a clear reference for separating the right hand thump rule and right hand grip rule.
Also I am thanking you for such a good site. It is this SCF that cleared my three year argument about AC. Electrons move to and fro in AC unlike DC where there is cumilation of electrons (which flows in one directions). I claimed the same thing when I was taught the AC generator at the school. No other site gave such a clear definition to me with a clear diagram.
Valchemishnu - India
With the right-hand thumb rule, you are emphasizing the direction of the item indicated by the thumb. With the right-hand rule, you could be either considering the motion in the direction of the fingers or the value in the direction of the thumb. The right-hand grip rule simply makes sure the person is thinking of gripping the wire or such.
But since the difference is trivial, it is more common to see "right-hand rule" stated.
I am glad you've found the site helpful to you. Best wishes for success in your studies.
Can electricity be generated in home?
Topic: Generating Electricity
October 23, 2011
i want know can electricity generated in home
Rohan - India
People use solar panels, wind turbines, and gasoline generators to generate electricity for the home. Unfortunately, it is often expensive to set up such a system.
Specific voltage conversion with wire size
Topic: AC Transformers
October 16, 2011
Please provide me with the laws of his birth simplified to convert 500 volts to 220 volts note that the number of alliances 20 laps and the type of binding sequence and the wire diameter 1.80 mm, and thank you
ali - USA
I'm sorry, but we don't have that information.
Want to use lightning as a power source
October 14, 2011
We doing an project in lightening as source of electrical energy. But we are obstructed a problem. That since it is a high voltage source, it has to be step down. But since it is a d.c it cannot step down directly. can you please help us.
The biggest problem in using lightning as a source of electrical power is the fact that it is often uncertain when the lightning bolt will strike. In an area where there are many thunderstorms, you might be able to set up a lightning rod to attract the lightning bolts. One idea was to have many such towers to increase the chances of a lightning strike.
Before you think of stepping down the voltage, you need to be able to store the power in some way.
One thought is to store the power in a huge capacitor, so that the DC can be discharged slowly at a lower voltage. However, a lightning bolt sends its power so fast that a capacitor cannot be fully charged.
An interesting article on the subject is: Harnessing Lightning and Using the Electricity.
I hope this gives you some ideas.
Is the direction of the current opposite during charging?
October 10, 2011
IN A 12 VOLT DC CIRCUIT IF CURRENT FLOWS FROM NEGATIVE TO POSITIVE. WHEN A BATTERY CHARGER IS CONNECTED TO A BATTERY DOES CURRENT FLOW FROM POSITIVE TO NEGATIVE?
BILL - USA
Yes, the current is in the opposite direction during charging than when during use or discharging. You can think of it as adding electrons to the chemicals that store the current.
Resistance when wire is bent
Topic: DC Circuits
October 4, 2011
you are doing very well, i am very thankful to you, i have a question sir .do bend in wire affect its electrical resistance? sir i have another question. describe a circuit which will give a continuously varying potential.
owais - Pakistan
When a wire is just curved around an object, the resistance does not change. However, when the wire is sharply bent, it stretches the metal and slightly changes the resistance. It would be an interesting experiment to try to measure the difference. I am sure it is very small.
By adding a variable resistorlike a rheostatin a series circuit, you can vary the potential.
Who was the father of transformer?
Topic: AC Transformers
September 16, 2011
Who was the father of transformer ?
Bhanu - India
In 1886, American William Stanley invented the induction coil, or what is known today as a transformer.
Topic: Electrical Charges
September 1, 2011
Evaluate A^B, where A and B are vectors in space with i, j, k as the unit vectors
Stephen - Nigeria
See Vectors in Gravity Equations for some information on using vectors.
Hopefully, this reader feedback has helped provide information about Electricity issues.
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