Class 10 Science - Chapter Magnetic effects of Electric Current NCERT Solutions | What precaution should be taken to avoid

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?

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.

Draw magnetic field lines around a bar magnet.

List the properties of magnetic field lines.

State Fleming’s left-hand rule.

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.

A student has difficulty reading the blackboard while sitting in the last row. What could be the defect the child is suffering from? How can it be corrected?

What are the necessary conditions for autotrophic nutrition and what are its by-products?

Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?

Compare and contrast the arrangement of elements in Mendeléev’s Periodic Table and the Modern Periodic Table.

What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series?

What kind of mirror – concave, convex or plain – would be best suited for use in a solar cooker? Why?

You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.

How can ethanol and ethanoic acid be differentiated on the basis of their physical and chemical properties?

The kidneys in human beings are a part of the system for

   (a) nutrition.                  (c) excretion.
   (b) respiration.              (d) transportation.

Explain why the planets do not twinkle.