A 120 V lamp-dimming circuit is controlled by a rheostat and protected – McqOptions

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1.	A 120 V lamp-dimming circuit is controlled by a rheostat and protected from excessive current by a 3 A fuse. To what minimum resistance value can the rheostat be set without blowing the fuse? Assume a lamp resistance of 20 ohms.
A.	40
B.	4
C.	2
D.	20
Answer» E.

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