Please refer to Chapter 14 Sources of Energy Class 10 Science Important Questions with solutions provided below. These questions and answers have been provided for Class 10 Science based on the latest syllabus and examination guidelines issued by CBSE, NCERT, and KVS. Students should learn these problem solutions as it will help them to gain more marks in examinations. We have provided Important Questions for Class 10 Science for all chapters in your book. These Board exam questions have been designed by expert teachers of Standard 10.
Class 10 Science Important Questions Sources of Energy Chapter 14
Short Answer: I
Question: What is biogas? Why is biogas considered as an ideal fuel for domestic use?
Answer: Gas which is produced by the decomposition of cow-dung and various plant materials in the absence of oxygen is called biogas. Biogas is considered as an ideal fuel because
(i) it does not produce smoke
(ii) its heating capacity is high
(iii) slurry left behind can be used as an excellent manure.
Question:Draw a labelled schematic diagram of a biogas plant. What use is made of the slurry left behind in biogas plants?
Answer:
The slurry left behind in biogas plant can be used as manure which works as an organic fertilizer.
Question: Firewood is our conventional fuel. List any four reasons for replacing it by the alternate sources of energy.
Answer: Firewood is our conventional fuel. It should be replaced by alternate sources of energy due to following reasons:
(i) It produces less heat on burning.
(ii) It produces lots of smoke.
(iii) Cutting down of trees causes depletion of forest leading to imbalance in nature.
(iv) Due to low calorific value of wood it requires a large quantity of wood to generate a suffcient amount of heat.
Question: Give two examples each of the following :
(i) Renewable sources of energy (ii) Non-renewable sources of energy
Answer: (i) Examples of renewable sources of energy are wind energy, solar energy, etc.
(ii) Coal, petroleum and natural gas are two examples of non-renewable sources of energy.
Question: List any four limitations of the energy obtained from oceans.
Answer: Limitations of the energy obtained from ocean are:
(i) Ocean thermal energy can only be utilise at the places located at coastal areas.
(ii) Electricity produced from this energy is very less.
(iii) Ocean thermal energy can only be utilised if the temperature dfference between the water at the surface and water at depth upto 2 km is 20°C.
(iv) Utilisation of this energy is limited only during day time with sufficient sunlight.
Question: Write two advantages of classifying energy sources as renewable and non-renewable.
Answer: The two advantages of classifying energy sources as renewable and non-renewable are:
(i) Increasing use of renewable energy sources rather then using non-reversible sources of energy.
(ii) A judicious use of non-renewable energy source so as to prevent its depletion.
Short Answer: II
Question: (a) Distinguish between renewable and nonrenewable sources of energy.
(b) Choose the renewable sources of energy from the following list : coal, biogas, sun, natural gas
Answer:
(b) Sun is a renewable source of energy.
Question: While discussing about coal and petroleum, a teacher told his students about PCRA’s (Petroleum Conservation Research Association) guidelines to save the fossil fuels while driving vehicles. Deepa was going to her school with her mother who was driving car. At the traffivc signal, when the light was red, Deepa suggested her mother to switch off the engine. After reading the above passage, answer the following questions :
(a) Fossil fuels are natural resources, then why do we need to conserve them?
(b) List any two ways of saving the fossil fuels.
(c) State two values exhibited by Deepa.
Answer: (a) Fossil fuels are natural resources but they are non-renewable and exhaustible. Also, it takes millions of years for their formation. So they must be conserved to provide energy for longer duration and for sustainable development.
(b) (i) Using public transport and walking for short distances.
(ii) Using solar energy over conventional sources of energy.
(c) Deepa is concerned about natural resources and environment and assertive in nature.
