Q1. What is a nuclear waste? What are the hazards of nuclear waste to living things?
Q2. Out of two solar cookers, one was covered by a plane glass slab and the other was left open. Which of the two solar cookers will be more efficient and why?
Q3. People living on hills often get sunburns on their skin. Which component of sunlight is responsible for this effect? Why is this effect generally not observed near sea level?
Q4. Increasing demand of fossil fuels has caused harm to our environments. List its three ill effects (disadvantages). Suggest three measures to reduce the consumption of fossil fuels.
Q5. Compare the advantages of generating energy from bio-mass than getting it from hydropower plant?
Q6. Define the process of nuclear fission. Write the steps involved in generating electricity in a nuclear reactor.
Q7. Explain the principle and working of a biogas plant.
Q8. Draw a neat diagram of a biogas plant and label
(i) inlet of slurry,
(ii) digester and
(iii) gas outlet.
Q9. (a) List any two criteria for selecting a good fuel.
(b) Explain how does burning of fossil fuels cause air and soil pollution.
Q10. ‘What is a good source of energy?
Q11. State the energy transformation taking place at hydropower plants. List two advantages of setting up hydropower plants.
Q12. Explain generation of electricity in a thermal power plant.
Q13. What is biomass? What can be done to obtain bioenergy using biomass?
Q14. Why is there a need to harness non-conventional sources of energy? Give two main reasons.
Q15. 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?
Q16. What is geothermal energy? How can it be used commercially? List in tabular form three distinguishing features between a thermal power plant and a geothermal power plant.
Q17. Mention why is it not possible to make use of solar cells to meet all our energy needs. State three reasons to support your answer.
Q18. (i) Write four characteristics used for selecting a suitable fuel.
(ii) ‘Gaseous fuels are preferred over solid fuels in chemical industries’. Comment.
Q18. State in brief the process of harnessing kinetic energy of the wind. Mention some limitations of harnessing wind energy on large scale.
Q19. (i) State one limitation of using solar energy available from solar cells.
(ii) What is’ the minimum wind velocity required to obtain useful energy from a windmill?
(iii) Define the term nuclear fission.