10th class electric current lesson questions with answers table 4marks question
Answers
Explanation:
Question 1
What is the direction of magnetic field lines outside a bar magnet ?
Answer:
From North pole to South pole.
Question 2
What does crowding of magnetic field lines indicate ?
Or
What does the degree of closeness of magnetic field lines near the poles signify ?
Answer:
Crowding of magnetic field lines indicates that magnetic field in that region is strong.
Question 3
At what place of the magnet are the magnetic field lines denser ?
Answer:
Near the poles of the magnet.
Question 4
What is meant by magnetic field ?
Answer:
The space around a magnet or current carrying conductor within which its influence can be felt by a magnetic substance like iron is called magnetic field.
Question 5
How is the direction of magnetic field at a point determined ?
Answer:
Direction of magnetic field is determined by a compass needle. The direction of magnetic field is towards the north pole of the compass needle at a point.
Question 6
What is SI unit of magnetic field ?
Answer:
tesla (T).
Question 7
What is the direction of magnetic field lines inside a bar magnet ?
Answer:
From South pole to the North pole.
Question 8
Define a magnetic field line ? (CBSE (All India) 2006, 2010, 2015)
Or
What are magnetic field lines ?
Answer:
It is a curve around a magnet or a current carrying straight conductor such that the tangent at any point on the curve gives the direction of magnetic field at that point.
Question 9
Give two uses of a magnetic compass.
Answer:
It is used to determine the direction of north and south of earth.
It is used to draw the magnetic field lines around a bar magnet.
Based on magnetic field due to current through a straight conductor
Question 10
How is the strength of the magnetic field around a wire related to the strength of the electric current flowing in the wire ?
Answer:
The strength of magnetic field B increases with the increase in the electric current I and vice-versa. That is, Bocl.