(A) (i) Draw the pattern of the magnetic field lines for the two parallel straight conductors carrying current of same magnitude 'I' in opposite directions as shown. Show the direction of magnetic field at a point O which is equidistant from the two conductors. (Consider that the conductors are inserted normal to the plane of a rectangular cardboard.)

(ii) In our houses we receive A.C. electric power of $220\text{ V}$. In electric iron or electric heater cables having three wires with insulation of three different colours - red, black and green are used to draw current from the mains.

(a) What are these three different wires called? Name them colourwise.

(b) What is the potential difference between the red wire and the black wire?

(c) What is the role of the wire with green insulation in case of accidental leakage of electric current to the metallic body of an electrical appliance?

OR

(B) (i) By using the given experimental set-up. How can it be shown that:

(a) a force is exerted on the current-carrying conductor AB when it is placed in a magnetic field.

(b) the direction of force can be reversed in two ways.

(ii) When will the magnitude of the force be highest?

(iii) State Fleming's left hand rule.

(A) (i) The pattern of the magnetic field lines for the two parallel straight conductors carrying current of same magnitude 'I' in opposite directions is shown below:

(ii) (a) The three different wires are called live wire (red), neutral wire (black), and earth wire (green).

(b) The potential difference between the red wire and the black wire is 220 V.

(c) The role of the wire with green insulation is to provide a safe path for the electric current to flow to the ground in case of accidental leakage of electric current to the metallic body of an electrical appliance.

OR

(B) (i) (a) A force is exerted on the current-carrying conductor AB when it is placed in a magnetic field because the magnetic field exerts a force on the moving charges in the conductor.

(b) The direction of force can be reversed in two ways: by reversing the direction of the current in the conductor or by reversing the direction of the magnetic field.

(ii) The magnitude of the force will be highest when the conductor is perpendicular to the magnetic field.

(iii) Fleming's left hand rule states that if the thumb, index finger, and middle finger of the left hand are stretched at right angles to each other, then the thumb will point in the direction of the force, the index finger will point in the direction of the magnetic field, and the middle finger will point in the direction of the current.