Physics M/J 07 QP1

[Ismail Breiwish]

Number 31 please. A thorough explanation would be appreciated.

 

[larina]

when switch S is closed the electromagnet(in the relay) becomes magnetised thus allowing the contacts to come closer.
lamp 1 turns ON cuz the current flows through it AND lamp 2 also turns 0N bcuz the current flows through it by the ''relay'' and their is a closed circuit

so both lamps will light....so it is (A).

 

[Ismail Breiwish]

when switch S is closed the electromagnet(in the relay) becomes magnetised thus allowing the contacts to come closer.
lamp 1 turns ON cuz the current flows through it AND lamp 2 also turns 0N bcuz the current flows through it by the ''relay'' and their is a closed circuit

so both lamps will light....so it is (A).

Yeah, I understand that, but I'm still unsure as to the nature of the change that the second circuit goes through. So when the electromagnet becomes magnetized it attracts both parts ends of the switch, which eventually come in contact with each other?

 

[PlanetMaster]

You don't need working of relay.
Think of it more easily.
When 'Switch S' is closed, the 'Relay' and 'Lamp 1' turns on.
The relay then turns 'Lamp 2' on.
So answer is A.