Which element describes two or more normally closed switches in series?

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Multiple Choice

Which element describes two or more normally closed switches in series?

Two normally closed contacts in series conduct current only when neither input is active. A normally closed (NC) contact closes (conducts) in its resting state and opens when actuated. With two NC contacts in series, the output is true only if both contacts are still closed, i.e., both inputs are inactive. If either input is activated, its NC contact opens and the circuit breaks, making the output false. In logic terms, the output is NOT A AND NOT B, which is equivalent to NOR(A, B). So this arrangement behaves as a NOR element: a true output only when both inputs are false.

Two normally closed contacts in series conduct current only when neither input is active. A normally closed (NC) contact closes (conducts) in its resting state and opens when actuated. With two NC contacts in series, the output is true only if both contacts are still closed, i.e., both inputs are inactive. If either input is activated, its NC contact opens and the circuit breaks, making the output false. In logic terms, the output is NOT A AND NOT B, which is equivalent to NOR(A, B). So this arrangement behaves as a NOR element: a true output only when both inputs are false.

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