If a relay is hermetically sealed with an opaque cover, which of ___

If a relay is hermetically sealed with an opaque cover, which of the following methods should be used to determine whether the relay is operating?

A. Shake the relay and listen for loose parts
B. Place your finger on the cover and feel the relay contact movement
C. Remove the cover and visually observe the relay contacts when the relay is activated
D. Activate the relay and observe whether a metal object is attracted by the magnetic field

Show Answer

Answer: B

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