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You measure it indirectly using a known load resistance and measuring supplied current. Loading of the ammeter should be known as well, and the load resistance should be made relatively small to get accurate results.
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If a 12v car battery has 0.04ohm internal resistance what is the battery terminal voltage when the battery delivers 40A?
011.1
The Storage battery of a car has an emf of 12 volt if the internal resistance of the battery is 0.4 resistance what is the maximum current that can be drawn from the battery?
You have to imagine the internal resistance as being in parallel with any load you connect. You get the maximum possible current when the load is zero. In this case, just apply Ohm's Law. That is, divide the voltage by the internal resistance.
Automobile batteries use low or high internal resistance?
I think you are asking why is it necessary for an automobile battery to have low internal resistance. That is because the internal resistance of a battery limits the amount of current it will produce. Imagine connecting a wire from the plus side of the batter to the minus side. Then, the amount of current the battery produces is the voltage of the battery divided by its internal resistance. So, if you take a flashlight battery and connect a wire between the two terminals, it might get a little warm. If you take a car battery cannot a wire between the two terminals, the wire will probably melt! (Don't try this!) If you take a lithium ion battery from your computer and short the two terminals, the battery will catch on fire. (Computer companies build extra resistance into the batteries to help to prevent that. So, why do cars need low internal resistance batteries? They need lots of current to start those large gasoline engines turning. You car battery does a tremendous amount of work to start your engine (and remember, energy and work are the same in physics).
How long should you charge your 12 volt auto battery 35 amps 13.5 volts DC?
I think you mean 35Ah (Ampere-hours) This depends on the amount of energy that can be stored. The amount of energy in car batteries is usually expressed in Ah, and depends on the voltage of the battery. In Europe, mostly 12V, 40Ah to 70Ah. Let's say a battery of 35Ah 12V (in reality, a fully charged lead-acid battery will have 12,65V over its open poles) needs to be fully charged. 35Ah means tha it can, theoretically, deliver 35A at 12V during 1 hour. That's is a total power storage of 12x35 = 420Wh = 1512kJ (kiloJoules) The amount of current flowing into the battery will charge (by an electrochemical process) the battery. So it's not really the voltage of the battery, but the current that's important. Unless you know the internal resistance of the battery, You can not really calculate this. But now practical. You can charge a car battery at a pretty high current, although quality deteriorates with higher currents (that's why professional chargers will use a pulse charger) , so your 13,5V will not be too high. Car generators can deliver up to 16Volts to a battery. What I suggest is this: measure the battery voltage, load the battery with the 13,5V, and measure again after 10 minutes. Check the voltage of the battery, and do not exceed 12,5V. Even better: Load the battery, and meanwhile measure the current and voltage. Now you can calculate the internal resistance of the battery. A word of caution. Car batteries contain a highly poisonous fluid, a mix of water an sulfuric acid. Don't play around with it, DON'T SHORT IT, don't reverse polarisation, This fluid causes severe burns. Be careful.
How do you check the headlamp resistance in th earth connection?
The resistance (ohms) between the headlamp "earth" connection and the vehicle battery NEGATIVE connection should be near zero. Although zero ohms is technically not possible in anything short of a superconductor, the resistance should not be much more than 1. If the resistance is much more than that, you should clean rust/corrosion from connectors and use some kind of rust inhibiting/conductive material to improve the conductive properties of the circuit. The above is true, but not easy. If in doubt of any ground connection in a car, just run another ground wire from the item to somewhere you know is a good ground (car frame, ground buss, negative battery cable, etc)
If a 12v car battery has 0.04ohm internal resistance what is the battery terminal voltage when the battery delivers 40A?
011.1
The Storage battery of a car has an emf of 12 volt if the internal resistance of the battery is 0.4 resistance what is the maximum current that can be drawn from the battery?
You have to imagine the internal resistance as being in parallel with any load you connect. You get the maximum possible current when the load is zero. In this case, just apply Ohm's Law. That is, divide the voltage by the internal resistance.
How is it possible to have a high current with a low voltage such as in a car battery if current equals Voltage divided by Reistance then shouldn't a low voltage produce a low current?
It's all relative. A battery has internal resistance. Batteries are not "ideal" voltage sources. If there is a "heavy" load on the battery (low resistance), the voltage you measure on the outside of the battery will be lower. A car battery is normally thought of as a 12 volt battery. When there is no load (disconnected) you can often measure in excess of 13 volts if it's fully charged. During normal cranking of the engine, the voltage can drop below 11 volts.
Automobile batteries use low or high internal resistance?
I think you are asking why is it necessary for an automobile battery to have low internal resistance. That is because the internal resistance of a battery limits the amount of current it will produce. Imagine connecting a wire from the plus side of the batter to the minus side. Then, the amount of current the battery produces is the voltage of the battery divided by its internal resistance. So, if you take a flashlight battery and connect a wire between the two terminals, it might get a little warm. If you take a car battery cannot a wire between the two terminals, the wire will probably melt! (Don't try this!) If you take a lithium ion battery from your computer and short the two terminals, the battery will catch on fire. (Computer companies build extra resistance into the batteries to help to prevent that. So, why do cars need low internal resistance batteries? They need lots of current to start those large gasoline engines turning. You car battery does a tremendous amount of work to start your engine (and remember, energy and work are the same in physics).
How can a car battery be so strong when it only has 12 volts just like some toys?
Even though the battery is 12 volts, look at the size difference. It has low internal resistance and can deliver 300 amperes to crank a car.
When Replacing 12v coil on 1998 Kubota engine wg750 could it have resistance type external wiring from coil to distributor or is resistance internal in coil?
A engine coil has a high internal resistance, the needing of a suplementar resistance may be advised to you by a car electrician, who works with such brand and model of your car.
Why would a car battery smoke?
Internal short in the lead plates, time for a new battery.
Can battery test good when bad?
With no load attached, a battery can measure full voltage (potential). However, as soon as a load is put on it (current s drawn), the internal resistance in a defective battery will also draw current thus reduce output. If this is a car battery, have your local service station or garage do a cranking power test; thisi will prove if the battery is good or not. Be sure to take you old defective battery to your local recyling depot as it contains lead (poisonous metal) adn corrosive Sulfuric acid). Cheers Malcolm
How do you measure battery acid in a car battery?
With a hydrometer which you can buy at any auto parts store.
How long should you charge your 12 volt auto battery 35 amps 13.5 volts DC?
I think you mean 35Ah (Ampere-hours) This depends on the amount of energy that can be stored. The amount of energy in car batteries is usually expressed in Ah, and depends on the voltage of the battery. In Europe, mostly 12V, 40Ah to 70Ah. Let's say a battery of 35Ah 12V (in reality, a fully charged lead-acid battery will have 12,65V over its open poles) needs to be fully charged. 35Ah means tha it can, theoretically, deliver 35A at 12V during 1 hour. That's is a total power storage of 12x35 = 420Wh = 1512kJ (kiloJoules) The amount of current flowing into the battery will charge (by an electrochemical process) the battery. So it's not really the voltage of the battery, but the current that's important. Unless you know the internal resistance of the battery, You can not really calculate this. But now practical. You can charge a car battery at a pretty high current, although quality deteriorates with higher currents (that's why professional chargers will use a pulse charger) , so your 13,5V will not be too high. Car generators can deliver up to 16Volts to a battery. What I suggest is this: measure the battery voltage, load the battery with the 13,5V, and measure again after 10 minutes. Check the voltage of the battery, and do not exceed 12,5V. Even better: Load the battery, and meanwhile measure the current and voltage. Now you can calculate the internal resistance of the battery. A word of caution. Car batteries contain a highly poisonous fluid, a mix of water an sulfuric acid. Don't play around with it, DON'T SHORT IT, don't reverse polarisation, This fluid causes severe burns. Be careful.
When a volumetr is connected in series with a battery what does it measure the ability to?
Measures the amperage of the current .Your battery is in series with your car amp meter .
Is a car battery a circuit?
Hi, there. A battery is a power supply, a source of potential difference which drives current. In itself, a battery is not a circuit, but if you attach it to a load (a resistance), then a current will form and a circuit is made!
