1)

 The  symbolic  form of the following circuit is (where p,q represents  switches S1 and S2 closed respectively )

162021108_m2.JPG


A) $(p\wedge q)\wedge (\sim p\wedge \sim q)=l$

B) $(p\wedge [q\wedge (\sim p\wedge \sim q)=l$

C) $(p\vee q)\vee (\sim p\wedge \sim q)=l$

D) $(p\vee [q\wedge (\sim p\wedge \sim q)=l$

Answer:

Option C

Explanation:

 Here , p,q represents switches S1 and S2 closed respectively,

 262021534_m4.JPG

 here, S1, S2 , (S1' and S2' ) are in parallel

 and S1'   and S2' are series

 $\therefore$     l= $(p\vee q)\vee (\sim p\wedge \sim q)$