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Under what circumstances can the terminal potential difference of a battery exceed its emf?
Wiki User
∙ 11y ago
"The potential difference between the terminals of a battery will equal the emf of the battery when there is no current in the battery. At this time, the current though, and hence the potential drop across the internal resistance is zero. This only happens when there is no load placed on the battery-that includes measuring the potential difference with a voltmeter! The terminal voltage will exceed the emf of the battery when current is driven backward through the battery, in at its positive terminal and out at its negative terminal."
Raheel Ahmed
Quaid i Azam University Islamabd
Physics Dept
Wiki User
∙ 11y ago
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What is terminal PD?
A terminal potential difference is the potential difference appearing across the terminals of a voltage source, such as a battery or a generator, which varies according to the load supplied.When the battery or generator is off load (i.e. no load is connected to it), the terminal potential difference is equal to the electromotive force of that battery or generator.The terminal potential difference tends to decrease as the load current increases, due to a corresponding increase in the internal voltage drop of the battery or generator.
A battery has a difference in potential energy between the positive terminal and negative terminal which units express this difference in energy?
That's a difference in electrical potential, not potential energy.It's described in units of "volts".
When is the terminal potential difference of a battery greater than its emf?
When it is being loaded.
A battery has a difference in potential energy between the positive terminal and negative terminal which units express the difference?
Volts. Volts is another term for potential.
How do you connect a voltmeter to a battery?
To measure the total emf simply connect the battery and voltmeter with the right terminals , but to measure the terminal potential difference which is less than the emf the voltmeter is connected in parallel with the battery
In a 1.5V battery taking the negative terminal as 0.0V what is the electrical potential energy of an electron leaving the negative battery terminal?
Somebody is trying a trick question! The electron that comes out of the negative terminal has zero potential energy. With respect to the positive terminal it has -1.5V of electrical potential energy, and so does every other electron at 0.0V whether or not they came out of the battery.
What is the difference between a positive terminal and negative terminal of a battery?
The positive + terminal is slightly larger.
Explain how potential difference in a battery is similar to a staircase?
The potential difference in a battery is like the height of the stairs. The amount of charge separated in a battery is like the mass moved up the stairs. The potential energy in the battery is due to both the potential difference (volts) and the amount of charge that has been separated (coulombs).
Why the dc average voltage is having negative value?
Voltage is synonymous with 'potential difference', and cannot have a positive or negative value (in the sense of charge). So what you are describing is 'potential', which can. So, for example, a battery whose positive terminal is earthed or grounded will indicate a negative potential if a voltmeter is connected between earth and its negative terminal.
The potential difference of a battery depends on having an excess number of electrons at the negative terminal and a deficient number of electrons at the positive terminal?
That is true but not very - the excess of electrons at the negative terminal is small. The important thing is that if you place a load (radio set, light bulb etc.) on the battery the electrons flow through the load and this movement is supported by energy supplied by chemical action in the battery.
How does potential difference make an electric current flow and what is the direction of that current?
Potential difference, voltage, is a force that will cause electrons (negative charges) to move if they can. Voltage is the motive power behind electron flow, and electron flow is the current. In a battery, we have voltage between (or across) the terminals from chemical energy inside. We don't have to have current flow to have the voltage. Some might think of voltage as "electrical pressure" because it is a force. That isn't a bad way to look at it. If we connect some wires and put a light bulb and a switch in series across the terminals of the battery, we have a circuit. If we close the switch, voltage, which was present all the time, will now cause electrons to flow through the wire and light the bulb. The battery has a positive terminal and a negative terminal. The positive terminal will take in electrons and the negative terminal will send them out. Current flows in only one direction. The potential difference created by the battery has energized the circuit and current flowed from the negative terminal of the battery, out through the circuit, and back to the positive one.
Why does a battery work?
A battery s a source of constant potential difference , this potential difference drives the electrons present in the wire and this constitutes current .Shortly the potential difference across the battery terminals does work on the conduction electrons present inside the conductor. Actually a battery is an electrolytic device ,after some time the electrolyte completely exhausts this state of battery is called as discharged state.
