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प्रश्न
Name the physical quantity whose unit is "ohm".
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उत्तर
Electrical resistance is the physical quantity whose SI unit is ohm.
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संबंधित प्रश्न
Graph showing the variation of current versus voltage for a material Ga As is shown in the figure. Identify the region of
(i) negative resistance
(ii) where Ohm's law is obeyed.
Is Ohm’s law universally applicable for all conducting elements? If not, give examples of elements which do not obey Ohm’s law.
A low voltage supply from which one needs high currents must have very low internal resistance. Why?
Ohm's law gives a relationship between:
(a) current and resistance
(b) resistance and potential difference
(c) potential difference and electric charge
(d) current and potential difference
The unit of electrical resistance is:
(a) ampere
(b) volt
(c) coulomb
(d) ohm
Fill in the following blank with suitable words:
Resistance is measured in .............. The resistance of a wire increases as the length ..............; as the temperature ..............; and as the cross-sectional area .............. .
The resistors R1, R2, R3 and R4 in the figure given below are all equal in value.
What would you expect the voltmeter A, B and C to read assuming that the connecting wires in the circuit have negligible resistance?
How much energy is consumed when a current of 5 amperes flows through the filament (or element) of a heater having resistance of 100 ohms for two hours? Express it in joules.
Calculate the current flowing through a wire of resistance 5 Ω connected to a battery of potential difference 3 V.
A wire of resistance 9 ohm having length 30 cm is tripled on itself. What is its new resistance?
A wire has a length of 2.0 m and a resistance of 5.0 Ω. Find the electric field existing inside the wire if it carries a current of 10 A.
How does an increase in the temperature affect the specific resistance of a :
(i) Metal and
(ii) Semiconductor ?
What is meant by the drift speed of free electrons?
State and define Ohm’s law.
Choose the correct alternative.
Which of the following is an ohmic conductor?
Obtain the macroscopic form of Ohm’s law from its microscopic form and discuss its limitation.
Assertion: The statement of Ohm’s law is K = IR.
Reason: V = IR is the equation which defines resistance.
The voltage - current readings of a certain material are shown in the table given below:
| Voltage (V) | 10 V | 20 V | 30 V |
| Current (I) | 2 A | 3 A | 4 A |
Study the table.
- State whether the conductor used is ohmic or non-ohmic.
- Justify your answer.
- State Ohm's law.
