Tag: electric current, potential difference and resistance
Questions Related to electric current, potential difference and resistance
Name the physical quantity of which the unit is ampere:
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Current.
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Capacitance
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Charge
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Voltage
An electric current is a flow of electric charge. In electric circuits this charge is often carried by moving electrons in a wire. It can also be carried by ions in an electrolyte, or by both ions and electrons such as in a plasma.
The SI unit for measuring an electric current is the ampere, which is the flow of electric charge across a surface at the rate of one coulomb per second. Electric current is measured using a device called an ammeter.
The unit of current is :
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ampere
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volt
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ohm
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coulomb
Current is measured in Coulomb/sec or Ampere.
In an electric circuit, current starts from the-
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Positive terminal
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Either of the two terminals
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Negative terminal
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Depends upon the circuit
The direction of an electric current is by convention the direction in which a positive charge would move. Thus, thecurrent in the external circuit is directed away from the positive terminal and toward the negative terminal of the battery. Electrons would actually move through the wires in the opposite direction.
The speed at which the current travels in a conductor, is nearly
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$3 \times 10^0 ms^{-1}$
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$3 \times 10^5 ms^{-1}$
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$4 \times 10^6 ms^{-1}$
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$3 \times 10^8 ms^{-1}$
Current travels in a conductor at a speed approximately equal to speed of light i.e. $3\times 10^8$ $ms^{-1}$.
Which of the following statements is true?
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Electricity can be created
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Electricity flows in a circuit with gaps
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Electricity is the flow of negative charge
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All of the above
(A) Option:- Electricity can be created. This statement is false because electricity is basically a form of energy that cannot be created nor be destroyed
In a cell, electrons move from:
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positive electrode to negative electrode.
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negative electrode to positive electrode.
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both A and B.
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electrons do not move and only negative charge moves from one place to another place.
In cells, electrons move from negative electrode to positive electrode and an electron has negative charge. So, we can say that negative charge flows from negative electrode to positive electrode. But, by convention flow of charges are measured only through positive charges.When an electron moves from point A to point B,an equal amount of positive charge moves from point B to point A.
Electric current is the flow of
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electrons
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protons
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neutrons
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none of these
Electric current is defined as the flow of electrons.
In electrolysis:
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positive ions move toward the positive electrode and negative ions toward the negative electrode.
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positive ions move toward the negative electrode and negative ions toward the positive electrode.
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both ions move toward both the electrodes in equal amounts until they are balanced.
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none of the above
As unlike charges attract each other and like charges repel each other. Thus in electrolysis, positive ions move towards the negative electrode whereas negative ions move toward the positive electrode.Hence option B is correct.
The direction of current is taken as
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The opposite to the direction of flow of current.
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Opposite to the direction of flow of protons.
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Opposite to the direction of flow of electrons.
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All
In a DC circuit when a switch is closed to operate the circuit, the electrons that cause the current:
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travel from the negative plate of the battery to the positive plate
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travel from the positive plate of the battery to the negative plate
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travel from one resistance to the next resistance
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travel from the negative plate of the battery to the positive plate inside the battery
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travel from one atom in the circuit to the next atom
In a DC circuit , when switch is closed , the free electrons in wire are drifted from negative plate of the battery to positive plate.