Magnetic Effects of Electric Current — Class 10 Science PYQs

(a) Describe an activity to show that a current carrying conductor, placed in an external magnetic field experiences a force.
(b) Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally towards the front wall from the back wall, is deflected by a strong magnetic field to your right side. Find the direction of the magnetic field.

(a) The pattern of magnetic field due to a current carrying wire depends upon the shape made by that wire. Justify.
(b) A current carrying straight wire AB is shown in the given diagram. Out of X, Y and Z on which point will the strength of magnetic field be maximum and why ?

Assertion (A) : No two magnetic field lines are found to cross each other.
Reason (R) : The compass needle cannot point towards two directions at the point of intersection of two magnetic field lines.

In our homes, we receive the supply of electric power through a main supply also called mains, either supported through overhead electric poles or by underground cables. In our country the potential difference between the two wires (live wire and neutral wire) of this supply is $220\mathrm{V}$.
(a) Write the colours of the insulation covers of the line wires through which supply comes to our homes.
(b) What should be the current rating of the electric circuit ($220\mathrm{V}$) so that an electric iron of $1\mathrm{kW}$ power rating can be operated ?
(c) (i) What is the function of the earth wire ? State the advantage of the earth wire in domestic electric appliances such as electric iron.
OR
(c) (ii) List two precautions to be taken to avoid electrical accidents. State how these precautions prevent possible damage to the circuit/appliance.

(a) The given figure shows the current passing through the straight conductor XY.
(i) Copy the diagram and draw the magnetic field lines when current flows from conductor X to Y.
(ii) Name and state the rule used in determining the direction of the magnetic field lines in the situation given above.
(iii) State Fleming's left hand rule. Using this rule, determine the direction of force applied on an electron entering a uniform magnetic field as shown in the figure.
OR
(b) (i) Define the term solenoid. Draw the pattern of the magnetic field lines in and around a current carrying straight solenoid. Mark on the pattern the (i) direction of current, (ii) direction of field lines near the ends of the solenoid, and (iii) region where the magnetic field is uniform.
(ii) How would you make an electromagnet using a current carrying solenoid ?

Strength of magnetic field produced by a current carrying solenoid DOES NOT depend upon :

The pattern of the magnetic field produced inside a current carrying solenoid is :

Q. Nos. 17 to 20 are Assertion – Reason based questions :
These questions consist of two statements – Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below :

Assertion (A) : The deflection of a compass needle placed near a current carrying wire decreases when the magnitude of an electric current in the wire is increased.
Reason (R) : Strength of the magnetic field at a point due to a current carrying conductor increases on increasing the current in the conductor.

(i) Two magnetic field lines do not intersect each other. Why ?
(ii) How is a uniform magnetic field in a given region represented ? Draw a diagram in support of your answer.

Draw the pattern of the magnetic field lines due to a straight current carrying conductor indicating the direction of current in the conductor and the direction of the corresponding magnetic field lines.