ICSE ICSE Class 7 - CISCE Question Bank Solutions for Physics

A boy fires a gun and another boy at a distance of 1020 m hears the sound of firing the gun 3 s after seeing its smoke. Find the speed of sound.

A boy on a hill A fires a gun. The other boy on hill B hears the sound after 4 s. If the speed of sound is 330 m s-1, find the distance between the two hills.

Write true or false for a given statement.

In an electromagnet, the core is made up of copper.

Write true or false for a given statement.

An electric bell uses an electromagnet.

Write true or false for a given statement.

An electromagnet with soft iron core is a temporary magnet.

Fill in the blank

 An electromagnet is used to separate large mass of ______ scrap.

Fill in the blank

The strength of the magnetic field of an electromagnet is increased by inserting a core of soft ______

Select the correct alternative

Electromagnets are made up of

Select the correct alternative

An electromagnet is used in 

Select the correct alternative

The purpose of armature in an electric bell is

What is an electromagnet?

Name the material of an electromagnet?

Draw a labelled diagram to make a soft iron bar as an electromagnet. Describe in steps the procedure ?

You are given a U shaped soft iron piece, insulated copper wire and a battery. Draw a circuit diagram to make a horse shoe electromagnet ?

Name two factors on which the strength of magnetic field of an electromagnet depends ?

State two ways by which the strength of magnetic field of an electromagnet can be increased ?

State two common uses of electromagnets  ?

Name a domestic device in which an electromagnet is used ?

Draw a neat and labelled diagram of an electric bell and describe its working ?

The incomplete diagram of an electric bell is given in fig. Complete the diagram and label its different parts ?