Class 10 Science - Chapter Magnetic effects of Electric Current NCERT Solutions | The phenomenon of electromagnetic induct

The magnetic field in a given region is uniform. Draw a diagram to represent it.

How does a solenoid behave like a magnet? Can you determine the north and south poles of a current–carrying solenoid with the help of a bar magnet? Explain.

Explain the underlying principle and working of an electric generator by drawing a labelled diagram. What is the function of brushes?

In Activity 13.7, how do we think the displacement of rod AB will be affected if (i) current in rod AB is increased; (ii) a stronger horse-shoe magnet is used; and (iii) length of the rod AB is increased?

A positively-charged particle (alpha-particle) projected towards west is deflected towards north by a magnetic field. The direction of magnetic field is

   (a) towards south                 (b) towards east
   (c) downward                       (d) upward

Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split ring in an electric motor?

Draw magnetic field lines around a bar magnet.

Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise. Apply the right-hand rule to find out the direction of the magnetic field inside and outside the loop.

Two circular coils A and B are placed closed to each other. If the current in the coil A is changed, will some current be induced in the coil B? Give reason.

List the properties of magnetic field lines.

Did Döbereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.

What is a good source of energy?

Why is diffusion insufficient to meet the oxygen requirements of multi-cellular organisms like humans?

What are trophic levels? Give an example of a food chain and state the different trophic levels in it.

What changes can you make in your habits to become more environment-friendly?

What is the difference between a reflex action and walking?

What is the importance of DNA copying in reproduction?

If a trait A exists in 10% of a population of an asexually reproducing species and a trait B exists in 60% of the same population, which trait is likely to have arisen earlier?

Why should a magnesium ribbon be cleared before burning in air?

Define the principal focus of a concave mirror.

Only variations that confer an advantage to an individual organism will survive in a population. Do you agree with this statement? Why or why not?

What is the role of decomposers in the ecosystem?

The breakdown of pyruvate to give carbon dioxide, water and energy takes place in

        (a) cytoplasm.               (c) chloroplast.
        (b) mitochondria.           (d) nucleus.

What can you as an individual do to reduce your consumption of the various natural resources?

What advantage over an aquatic organism does a terrestrial organism have with regard to obtaining oxygen for respiration?

A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.

Why do you think that there should be equitable distribution of resources? What forces would be working against an equitable distribution of our resources?

Use Mendeléev’s Periodic Table to predict the formulae for the oxides of the following elements:

    K,     C,      AI,      Si,      Ba.

Why should curd and sour substances not be kept in brass and copper vessels?

We saw in this chapter that there are four main stakeholders when it comes to forests and wildlife. Which among these should have the authority to decide the management of forest produce? Why do you think so?