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प्रश्न
Which unit could be used to measure current?
(a) Watt
(b) Coulomb
(c) Volt
(d) Ampere
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उत्तर
Ampere
It is the SI unit of electric current.
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संबंधित प्रश्न
Calculate the number of electrons constituting one coulomb of charge.
Choose the correct alternative and rewrite the following sentence.
When the resistance of a conductor increases, the current will ________ increase.
Fill in the folloing blank with suitable words:
Current is measured in ............... using an ............... placed in ............... in a circuit.
What is the conventional direction of the flow of electric current? How does it differ from the direction of flow electrons?
Consider the circuit given below when A, B and C are three identical light bulbs of constant resistance. 
(a) List the bulbs in order of increasing brightness.
(b) If C burns out, what will be the brightness of A now compared with before?
(c) If B burns out instead, what will be the brightness of A and C compared with before?
State the S.I. unit of current.
Two resistors of 2.0 Ω and 3.0 Ω are connected (a) in series (b) in parallel, with a battery of 6.0 V and negligible internal resistance. For each case draw a circuit diagram and calculate the current through the battery.
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(i) the internal resistance and (ii) e.m.f. of the cell.
The following circuit diagram shows three resistors 2 Ω, 4 Ω and R Ω connected to a battery of e.m.f 2V and internal resistance 3 Ω. If the main current of 0.25 A flows through the circuit, find:
- the p.d. across the 4 Ω resistors,
- the p.d. across the internal resistance of the cell,
- the p.d. across the R Ω or 2 Ω resistors, and
- the value of R.
Tick(✓) the correct choice in the following:
The outer casing of an electric iron is generally connected to earth in order
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(a) Calculate the current flowing through the conductor.
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Find the effective resistance in the following circuit diagrams (Fig.):
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has the larger working resistance?
| Appliances | Voltage (V) | Power (W) |
| (a) Washing machine | 250 | 3000 |
| ( b) Television | 240 | 160 |
| (c)240 | 240 | 1500 |
| ( d) Hair curler | 250 | 20 |
| ( e) Car head lamp | 12 | 36 |
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Coulomb is the SI unit of ____________.
