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25 Cards in this Set
- Front
- Back
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Unit of charge? |
the SI unit of charge is coulomb( symbol C) 1mC =10¯³ C 1micro C = 10¯6 C1nC = 10¯9 C |
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What is charge? |
The quantity of charge on a body is determined by the number of electrons in the body. Is the number of electrons in the body is less that is positively charged excess then the body is negatively chargedIt is denoted by letter Q |
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1C = ? electrons |
1/1.6×10¯9 |
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Define current. |
Current is defined as the rate of flow of charge. The current flowing in a conductor is amount of charge flowing per second across any cross section of it. Denoted by letter I I = Q/t |
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What is the unit of current? Define it. |
The SI unit of current is ampere. (Symbol A) 1 ampere is the current which flows in a conductor when 1 Columbus charge passes in one second through it. 1A = 1C/1s |
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What is flow of current? |
In metals the moving charges are the free electrons which constitutes the current while in electrolytes and ionised gases both the positively charged ions and negatively charged ions are moving charges which forms current |
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Define potential at a point. |
The potential at a point it is defined as the amount of work done per unit charge in bringing positive test charge some infinity to that pointIt is denoted by letter V V=W/Q |
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What is the SI unit of electric potential? Define. |
The SI unit of electric potential is joule /coulomb and the given name is volt. The potential at a point is said to be 1 volt when one joule of work is done in bringing one column charge from infinity to that point. |
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What is potential difference? |
The potential difference between two points is equal to the work done per unit charge in moving a positive test charge from one point to another. Va - Vb = W/Q |
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What is the SI unit of potential difference? |
The potential difference between two points is said to be 1 volt if the work done in moving 1 coulomb charge from one point to another is 1 Joule. 1V = 1JC¯ Va - Vb = W/Q |
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What is Resistance? |
The obstruction refer to the flow of current by the conductor or wire is called steps resistance. |
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What is the cause of resistance? |
When a metal is formed its atoms lose electrons from its outer Orbit. A metal has a large number of electrons and an equal number of fixed positive ions point the positive ions do not move, while the electrons move almost freely inside the metal. they move at random comma colliding amongst themselves and with the positive ions as in any direction. |
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State Ohm's law. |
According to Ohm's law, the current flowing in a conductor is directly proportional to the potential difference applied across the two ends provided that the the physical conditions and the temperature of the conductor remains constant. |
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Define 1 Ohm. |
The resistance of a conductor is said to be 1 Ohm if 1 ampere current flows through it when a potential difference of 1 volt is applied across the ends of the conductor. |
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What is conductance? |
The reciprocal of resistance is conductance. It is denoted by letter G. |
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What is electromotive force? |
When no current is drawn from a cell such that when the cell is in the open circuit the potential difference between the terminals of the cell is called its electro motive force. |
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What is electromotive force of a cell? |
The EMF of a cell is defined as the energy spent Per unit charge in taking a positive test charge around the complete circuit of the cell. |
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What is terminal voltage? |
The Terminal voltage of a cell is defined as the work done Per unit charge in carrying a positive charge around the circuit connected across the terminals of the cell. |
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What is voltage drop in the cell? |
The work done Per unit charge in carrying a positive test charge through the electrolyte is called the voltage drop in cell. |
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What is internal resistance of a cell? |
The resistance offered by the electrolyte inside the cell, to the flow of the current, is called the internal resistance of a cell. |
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Factors affecting internal resistance of a cell. |
1. The surface area of the electrodes 2. The distance between the electrodes 3. The nature and concentration of the electrolyte4. The temperature of the electrolyte |
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What is the SI unit of electrical power?Define it. |
The SI unit of electrical power is VA or Js¯¹ or W 1 watt is the electric power consumed when a current of 1 ampere flows through a circuit having a potential difference of 1 volt. |
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What are the two quantities of an appliances? |
1. The resistance of its filament or element when it is in use2. The safe limit of the current which can flow through the appliance while in use |
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What is the unit of household consumption of electrical energy? |
The electrical energy is sold in units of kilowatt hour. Thus the unit in which the consumer pays the cost of electrical energy consumed in kilowatt hour |
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What are the three factors on which the amount of heat produced in a wire depends upon? |
1. The amount of current passing through the wire. 2. The resistance of the wire.3. The time for which current is passed in the wire. |
