Class 10 Magnetic effects of current - Practice Worksheet
One marks questions
Question 1 How can you show that the magnetic field produced by a given electric current in the wire decreases as the distance from the wire increases? Solution
If we slowly take away a magnetic compass from a current carrying conductor,the deflection of the compass decreases. this clearly shows that magnetic field decreases as we increase the distance of the wire{current}
Question 2 What is the advantage of the third wire of earth connection in domestic appliances? Solution
It prevents us from electric shock. Bsaically third wire of earth connection in domestic electrical application conducts charge that appears on the body of appliance into the earth. So saving the user from an electric shock.
Question 3 How is the strength of the magnetic field at a point near a wire related to the strength of the electric current flowing in the wire? Solution
The strength of the magnetic field is directly propotional to the current flowing through the wire.
Question 4 On what effect of an electric current does an electromagnet work? Solution
agmetic Effect of Current
Two marks questions
Question 5. With the help of a neat-diagram, describe how you can generate induced current in a circuit. Question 6 Explain terms: (a) overloading and (b) short-circuiting Solution
Overloading
If more electrical appliances of high power rating like electric iron box, electric cooker, electric heater, air conditioner etc., are switched on at the same time, they draw an extremely large current from the circuit is called overloading. Check Animation here
Short-circuiting
Sometimes, the live and neutral wires come in the direct contact due to defective or damaged wiring. When this happens, the resistance of the circuit becomes almost zero and a very large current flows through it. This is known as Short Circuit.
Question 7 List in tabular form two major differences between electric motor and electric generator. Solution
Question 8 Explain the function of earth wire. Why is it necessary to earth metallic appliances? Question 9 All household appliances are connected in parallel. List two advantages of this type of arrangement. Solution
(i) To have equal potential difference across each appliance.
(ii) Each appliance has separate switch to the flow of current through it, so that each circuit can work independently
Three marks questions
Question 10 Explain briefly two different ways to induce current in a coil. State the rule which determines direction of induced current. Question 11 (a) A stationary charge is placed in a magnetic field. Will it experience force? Give reason and justify your answer.
(b) On what factors does the direction of force experienced by a current carrying conductor when placed in a magnetic field depends?
(c) Under what conditions is the force experienced by a current carrying conductor placed in a uniform magnetic field is maximum. Solution
a) No, a magnetic field exerts a force only on moving charges.
b) The direction of force experienced by a current carrying conductor placed in a magnetic field depends on the direction of the current in the conductor and the direction of the applied magnetic field. This is given by Fleming's left hand rule.
c) The force experienced by a current carrying conductor is maximum when the current and magnetic field are at right angles to each other.
Question 12 List four important features of domestic electric circuit. Draw a diagram of common domestic circuit showing live, neutral and earth wires.
