Class 10 Science - Chapter Sources of Energy NCERT Solutions | What is a good source of energy?

Can any source of energy be pollution-free? Why or why not?

What are the limitations of the energy that can be obtained from the oceans?

If you could use any source of energy for heating your food, which one would you use and why?

On what basis would you classify energy sources as

(a) renewable and non-renewable?
(b) exhaustible and inexhaustible?

Are the options given in (a) and (b) the same?

Which of the following is not an example of a bio-mass energy source?

      (a) wood                     (b) gobar-gas
      (c) nuclear energy      (d) coal

Hydrogen has been used as a rocket fuel. Would you consider it a cleaner fuel than CNG? Why or why not?

What are the disadvantages of fossil fuels?

Compare and contrast fossil fuels and the Sun as direct sources of energy.

Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choices.

Name two energy sources that you would consider to be renewable. Give reasons for your choices.

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

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.

You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?

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

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

Why is sodium kept immersed in kerosene oil?

What is the need for a system of control and coordination in an organism?

How much energy is given to each coulomb of charge passing through a 6 V battery?

Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?

Nitrogen (atomic number 7) and phosphorus (atomic number 15) belong to group 15 of the Periodic Table. Write the electronic configuration of these two elements. Which of these will be more electronegative? Why?

The xylem in plants are responsible for

         (a) transport of water.                   (c) transport of amino acids.
         (b) transport of food.                     (d) transport of oxygen.

What would be the consequences of a deficiency of haemoglobin in our bodies?

In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?

How is the amount of urine produced regulated?