- AIt breaks the circuit
- BIt open the circuit by pulling in an iron contact
- CIt closes the circuit by pulling in an iron contact
- DBoth A or C
Explanation:
They are ways of switching using a low current to use an electromagnet to close or open a spring steel contact.They are often used to isolate a user from a high voltage that needs to be switched, using low current, low voltage to operate the relay, rather than having a user come in direct proximity to the higher voltage that needs to be switched.When the current through the electromagnet of a relay reaches a particular value it either breaks the circuit by repllening or closes the circuit by pulling in an iron contact.
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The relation among u, v and f for a mirror is:
The resistance of a wire is R. If the length of the wire is doubled by stretching, then the new resistance will be
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(a) 2R |
(b) 4R |
(c) R |
(d) |
A small sphere carrying a charge ‘q’ is hanging in between two parallel plates by a string of length L. Time period of pendulum is
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(a) |
(b) |
(c) |
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