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प्रश्न
<p> Define the unit of electric current (or Define ampere).
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उत्तर
The SI unit of electric current is ampere.
When one coulomb of charge flows through any cross-section of a conductor in one second, the electric current flowing through it is said to be one ampere.
1 ampere= `(1coulomb)/(1second)`
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संबंधित प्रश्न
Choose the correct alternative and rewrite the following sentence.
When the resistance of a conductor increases, the current will ________ increase.
How many milliamperes as there in 1 ampere?
Write down the formula which relates electric charge, time and electric current
Which instrument is used to measure electric current? How should it be connected in a circuit?
A student made an electric circuit shown here to measure the current through two lamps.
Are the lamps in series or parallel?
(a) Are the lamps in series or parallel?
(b) The student has made a mistake in this circuit. What is the mistake?
(c) Draw a circuit diagram to show the correct way to connect the circuit. Use the proper circuit symbols in your diagram.
An electric circuit consisting of a 0.5 m long nichrome wire XY, an ammeter, a voltmeter, four cells of 1.5 V each and a plug key was set up.
(i) Draw a diagram of this electric circuit to study the relation between the potential difference maintained between the points 'X' and 'Y' and the electric current flowing through XY.
In the circuit shown below, the voltmeter reads 10 V.
(a) What is the combined resistance?
(b) What current flows?
(c) What is the p.d. across 2 Ω resistor?
(d) What is the p.d. across 3 Ω resistor?
Complete the following sentence:
Fuse wire has a ............ Melting point and it is made of an alloy of ......... and if the current in a circuit rises too high, the fuse wire ...........
Two resistors of 4 Ω and 6 Ω are connected in parallel. The combination is
connected across a 6 volt battery of negligible resistance. Calculate:
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Electromotive force
A wire is passed through a piece of cardboard as shown in fig .. An electric current flows vertically down the wire and then flows back up. The two sections of the write are observed to repel each other.
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Match the items in column-I to the items in column-II:
| Column - I | Column - II | ||
| (i) | electric current | (a) | volt |
| (ii) | potential difference | (b) | ohm meter |
| (iii) | specific resistance | (c) | watt |
| (iv) | electrical power | (d) | joule |
| (v) | electrical energy | (e) | ampere |
The flow of electric charge per unit time is called potential difference.
Match the items in column-I to the items in column-II:
| Column - I | Column - II |
| (i) electric current | (a) volt |
| (ii) potential difference | (b) ohm meter |
| (iii) specific resistance | (c) watt |
| (iv) Electrical power | (d) joule |
| (v) electrical energy | (e) ampere |
