Class 10 Science - Chapter Magnetic effects of Electric Current NCERT Solutions | When does an electric short circuit occu

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.

What are the environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption?

The anther contains

(a) sepals.
(b) ovules.
(c) pistil.
(d) pollen grains.

What is the common name of the compound CaOCl₂?

A spherical mirror and a thin spherical lens have each a focal length of –15 cm. The mirror and the lens are likely to be

(a) both concave.
(b) both convex.
(c) the mirror is concave and the lens is convex.
(d) the mirror is convex, but the lens is concave.

Explain the importance of fossils in deciding evolutionary relationships.

Which of the following groups contain only biodegradable items?

(a) Grass, flowers and leather
(b) Grass, wood and plastic
(c) Fruit-peels, cake and lime-juice
(d) Cake, wood and grass

Why are we looking at alternate sources of energy?

Draw the structure of a neuron and explain its function.

Will current flow more easily through a thick wire or a thin wire of the same material, when connected to the same source? Why?

Why does the Sun appear reddish early in the morning?