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प्रश्न
Differentiate between Conductors and insulators.
उत्तर
| Conductors | Insulators |
|
Those substances through which electricity can flow are called conductors. |
Those substances through which electricity cannot flow are called insulators. |
| Electrical resistances of conductors are very low. | Electrical resistances of insulators are infinitely very high. |
|
They contain a large number of free electrons. |
They do not contain free electrons. |
|
Generally, metals are conductors. E.g. silver, copper, aluminium |
Generally non – metals are insulators. E.g. wood, rubber, plastic |
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संबंधित प्रश्न
State Fleming’s left-hand rule.
State whether the following statement is true or false
The field at the centre of a long circular coil carrying current will be parallel straight lines.
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State the rule to determine the direction of a force experienced by a current-carrying straight conductor placed in a magnetic field which is perpendicular to it.
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State the form of magnetic field lines around a straight current-carrying conductor.
State whether the following statement is true or false:
The magnetic field inside a long circular coil carrying current well be parallel straight lines.
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State and explain the Clock face rule for determining the polarities of a circular wire carrying current.
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List three ways in which the magnetic field strength of a current-carrying solenoid can be increased?
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(a) will decrease
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For Fleming's left-hand rule, write down the three things that are 90° to each other, and next to each one write down the finger or thumb that represents it.
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Which way does the wire in the diagram below tend to move?
State condition when magnitude of force on a current carrying conductor placed in a magnetic field is zero?
Name and state the law which is used to determine the direction of force on a current carrying conductor placed in a magnetic field.
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What happens when a current is passed in the coil?
i) Which principle is explained in this figure?
ii) Which rule is used to find out the direction of a force in this principle?
iii) In which machine this principle is used? Draw a diagram showing working of that machine
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State Fleming's left handle rule.
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When will the couple acting on the coil be
- maximum
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The force on the wire due to the magnet is directed ____________.
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What do you know about Michael Faraday?
Assertion (A): A magnetic field exerts a force on a moving charge in the same direction as the direction of the field itself.
Reason (R): The direction of force is given by Fleming’s left-hand rule.
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Two LED bulbs of 10W and 5W are connected in series. If the current flowing through 5W bulb is 0.005A, the current flowing through 10W bulb is ______.
