Circuits-Output
Question 1 |
A two-way switch has three terminals a, b and c. In ON position (logic value 1), a is connected to b, and in OFF position, a is connected to c. Two of these two-way switches S1 and S2 are connected to a bulb as shown below.
Which of the following expressions, if true, will always result in the lighting of the bulb ?
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Question 1 Explanation:
The bulb will be on when both the switch S1 and S2 are in same state, either OFF (or) ON:
From this we can clearly know that given is EX-NOR operation i.e.,
(S1⊙S2) = (S1⊕S2)'
From this we can clearly know that given is EX-NOR operation i.e.,
(S1⊙S2) = (S1⊕S2)'
Question 2 |
The line T in the following figure is permanently connected to the ground.
Which of the following inputs (X1 X2 X3 X4) will detect the fault?
0000 | |
0111 | |
1111 | |
None of these |
Question 2 Explanation:
Since the problem is in the link T which is connected as input to NOR gate. So to check link T we have to make the output dependent on T by deactivating link M. So to deactivate link M, the output at M should be 0, as link M is input to NOR gate. So, to output at M as 0,
X1 = 1
X2 = 1
X3 = 1
X4 = 0
∴ None of the given option is correct.
There are 2 questions to complete.