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प्रश्न
The unit of electrical resistance is:
(a) ampere
(b) volt
(c) coulomb
(d) ohm
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उत्तर
(d) ohm
The unit of electrical resistance is ohm.
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संबंधित प्रश्न
What will be the change in the current if the potential difference is kept constant and the resistance of the circuit is made four times?
- It will remain unchanged.
- It will become four times.
- It will become one-fourth.
- It will become half.
Find the expression for the resistivity of a material and state the SI unit of resistivity.
What is the necessary condition for a conductor to obey Ohm’s law?
What is an ohmic resistor? Give one example of an ohmic resistor. Draw a graph to show its current voltage relationship. How is the resistance of the resistor determined from this graph?
An electric bulb draws 1.2 A current at 6.0 V. Find the resistance of filament of bulb while glowing.
A wire of resistance 3 ohm and length 10 cm is stretched to length 30 cm. Assuming that it has a uniform cross section, what will be its new resistance?
In the circuit shown in the figure, find the total resistance of the circuit and the current in the arm AD.
Calculate the electric field in a copper wire of cross-sectional area 2.0 mm2 carrying a current of 1 A.
The resistivity of copper = 1.7 × 10–8 Ω m
Consider the sacle of voltmeter shown in the diagram and answer the following questions :
(a) What is the least count of the voltmeter?
(b) What is the reading shown by the voltmeter ?
(c) If the voltmeter is connected across a resistor of 20 `Omega` how much current is flowing through the resistor?
Fig. represents the circuit used for the verification of Ohm's law. Label the parts from A to F. state the function of each.
State and define Ohm’s law.
State the limitations of Ohm’s law.
What are non-ohmic conductors? Give one exmaple. Draw a current-voltage graph for a non-ohmic conductor.
Choose the correct alternative.
Which of the following is an ohmic conductor?
Define Current density.
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.
