Q. 1. Mention the angle between a current carrying conductor and magnetic field for which the force experienced by this current carrying conductor placed in magnetic field is largest.
Ans. The angle between current carrying conductor and magnetic field is 90 deg.
Q. 2. Mention the advantage of A.C. over D.C. for long distance transmission.
Ans. A.C. can be easily transmitted over long distances without much loss of energy.
Q. 3. In domestic electric circuit, with which wire do we connect a fuse ?
Ans. Live wire.
Q. 4. List any one point of difference between A.C. and D.C.
Ans. Direct current always flows in one direction and alternating current reverses its direction periodically.
Q. 5. Name the physical quantities which are indicated by the direction of thumb and forefinger in the Fleming s right hand rule ?
Ans. Direction of motion of the conductor and direction of field.
Q. 6. Name the device used to prevent damage to the electrical appliances and the domestic circuit due to overloading.
Ans. Electric fuse.
Q. 7. Name the type of current : (a) Used in household supply. (b) Given by a cell.
Ans. (a) Alternating current 1/2 (b) Direct current.
Q. 8. State the value of potential difference between the live wire and the neutral wire in our country.
Ans. 220 V
Q. 9. State the effect on the strength of magnetic field produced at a point near a straight conductor if the electric current flowing through it increases.
Ans. The strength of the magnetic field increases.
Q. 10. State a difference between the wires used in the element of an electric heater and in a fuse.
Ans. The melting point of the wire used in heater elements is high while a fuse wire has low melting point.
Q. 11. State the observation made by Oersted on the basis of his experiment with current carrying conductors.
Ans. Every current carrying conductor has a magnetic field around it.
Q. 12. Suggest one way of discriminating a wire carrying current from a wire carrying no current.
Ans. Bring a magnetic needle near the wire, a current carrying wire will produce a deflection in the needle whereas a wire without current will not.
Q. 13. List two sources of magnetic fields. Magnet, moving charges, electric current. (any two) State the effect of a magnetic field on the path of a moving charged particle
Ans: It can deflect the path of the charged particle.
Q.14. An alternating current has a frequency of 50 Hz. How many times does it change its direction in one second ?
Ans: 100 times.
Q.15. State the use of earth wire in domestic electric circuit.
Ans: To ensure that any leakage of current to the metallic body of the appliance does not give shock to the user. Q.16. State the conclusions that can be drawn from the observation that a current carrying wire deflects a magnetic needle placed near it.
Ans: A magnetic field exists around it. Read full papers