State two ways to increase the force on a current-carrying conductor in a magnetic field.

Fill in the following blanks with suitable words:

(a) Fleming's Rule for the motor effect uses the ............... hand.

(b) A motor contains a kind of switch called a ............ which reverses the current every half ............ .

A current-carrying conductor is placed perpendicularly in a magnetic field. Name the rule which can be used to find the direction of force acting on the conductor.

Name one device whose working depends on the force exerted on a current-carrying coil placed in a magnetic field.

State Fleming's left-hand rule. Explain it with the help of labelled diagrams.