Read the following passage and answer any four questions from (a) to (e). A student fixes a sheet of white paper on a drawing board. He places a bar magnet in the centre of it. He sprinkles some iron filings uniformly around the bar magnet. Then he taps the board gently and observes that the iron filings arrange themselves in a particular pattern.
Question 1(a)
Why do the iron fillings arrange themselves in a particular pattern:
(i) Due to external force applied on the magnet.
(ii) Due to force exerted by the magnet outside the magnetic field.
(iii) Due to the force exerted by magnet within its magnetic field.
(iv) Due to pressure of magnetic field.
Answer:
The iron filings align themselves in a circular pattern along the magnetic in a circular pattern. This is due to the force exerted by the magnet within its magnetic field.
So, the correct answer is (iii)
Question 1(b)
What do the lines along which the iron fillings align represent:
(i) North pole and south pole of the magnet
(ii) Strength of the magnet
(iii) Magnetic field lines
(iv) Gravitational force.
Answer:
The iron filings align themselves in a circular pattern along the magnetic in a circular pattern and these lines represent the magnetic field lines.
So, the correct answer is (iii)
Question 1(c)
What does the crowding of iron filings at the end of the magnet indicate?
(i) magnetic field is strongest near the poles of the magnet.
(ii) magnetic field is weakest near the poles of the magnet.
(iii) There is no significant magnetic field at the poles of the magnet.
(iv) The significance of polarity
Answer:
The stronger the magnetic field , the closer the field lines are to each other.
Magnetic field lines are crowded towards the poles because the magnetic field is stronger near the poles.
So, the correct answer is (i)
Question 1(d)
The close field lines indicate:
(i) Magnetic field in that region is weak
(ii) Magnetic field in that region is strong.
(iii) Magnetic field in that region is zero.
(iv) North and south poles are closer.
Answer:
The stronger the magnetic field , the closer the field lines are to each other.
So, the correct answer is (ii)
Question 1(e)
What is SI unit of magnetic field:
(i) Pascal
(ii) Nm2
(iii) Tesla
(iv) No unit
Answer:
The SI unit of magnetic field is tesla.
So, the correct answer is (iii)
