Worksheet FA

Read the passage and answer the question that follows.

About Induction

We have learnt that when electrical current flows in a conductor, a magnetic field is created around it. In a similar manner, if we move a wire inside a magnetic field there will be an electrical current generated in the wire. Current is produced when a conductor is moved through a magnetic field because the magnetic lines of force are applying a force on the free electrons in the conductor and causing them to move. This process of generating current in a conductor by placing the conductor in a changing magnetic field is called induction. This is called induction because there is no physical connection between the conductor and the magnet. The current is said to be induced in the conductor by the magnetic field. One requirement for this electromagnetic induction to take place is that the conductor, which is often a piece of wire, must be perpendicular to the magnetic lines of force in order to produce the maximum force on the free electrons. The direction that the induced current flows is determined by the direction of the lines of force and by the direction the wire is moving in the field.

Why is current produced when a conductor rod is moved between opposite poles of a magnet?

Which of the following will be used to make a fuse wire?

Which of the following electromagnets will be the strongest?

Which of these appliances does not work on magnetic effect of current?

Working of a fuse is based on:

Birds sitting on overhead cables do not get electric shock. Why?

If the fuse is made of copper wire, what could happen?

Air conditioners and water heaters are connected to the power sockets at home. What happens if they are mistakenly plugged into normal sockets?