Tricky wording in electrical circuits question

[supernova1203]

Homework Statement

Homework Equations

The Attempt at a Solution

When it says, without changing the circuit, does it mean adding something else that is extra or does that mean i have to solve it without closing the switch?

 

[ehild]

The switch belongs to the circuit and you can use it.

ehild

 

[truesearch]

What will happen when you
a) close the switch
b) open the switch ?

 

[CWatters]

Remember that what makes dynamos and motors work is changing flux not constant flux.