A sensitive instrument susceptible to magnetic infiuence can be protected from external magnetic field by
enclosing it in a thick walled iron box
wrapping it with an insulator
by placing it inside a glass case
by surrounding it with fine copper gauze
Correct Answer :
A. enclosing it in a thick walled iron box
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enclosing it in a thick walled iron box
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by placing it inside a glass case
by surrounding it with fine copper gauze
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