(English Medium) ICSE Class 9 - CISCE Question Bank Solutions

A longitudinal wave travels at a speed of 0.3 m s^-1 and the frequency of wave is 20 Hz. Find the separation between two consecutive compressions. 

Distinguish between a closed circuit and an open circuit, with the use of suitable labelled diagrams. 

What is a lodestone? 

What is a natural magnet? State two limitations of a natural magnet. 

What is an artificial magnet? State two reasons why do we need artificial magnets .

How will you test whether a given rod is made of iron or copper?

[Hint : Iron rod gets magnetised when placed near a bar magnet by magnetic induction, while copper rod does not get magnetised]

Explain what you understand by magnetic induction. What role does it play in attraction of a piece of iron by a magnet?

Explain the following :

When two pins are hung by their heads from the same pole of a magnet, their pointed ends moves apart.

Explain the following :

Several soft iron pins can cling, one below the other, from the pole of a magnet.

Explain the following :

The north end of a freely suspended magnetic needle gets attracted towards a piece of soft iron placed a little distance away from the needle.

Explain why iron filings which are sprinkled on a sheet of cardboard placed over a bar magnet take up a definite pattern when cardboard is slightly tapped.

Can two magnetic field lines intersect each other? Give reason to your answer.

In following figure, draw at least two magnetic field lines between the two magnets.

(a)

In following figure, draw at least two magnetic field lines between the two magnets.

(b)

Sketch four magnetic field lines as obtained in a limited space on a horizontal plane in the earth's magnetic field alone.