# Conceptual's Questions for Source of energy

Question 1
Answer these questions on solar energy
(a) Why are black surface utilized for making solar cookers?
(b) What is solar cell? Name two materials mostly used for making solar cells?
(c) what are advantages and limitation of solar cooker?
(d) what is a solar power plant? Name one such plant in our Country
(e) what is the maximum temperature attained in a concave reflector type solar cooker?
(f) A student constructed a box type solar cooker. He found that it did not work efficiently. What could this be due to? Give any four possible mistakes in the construction and operation of the cooker.

Question 2
How were fossil fuels formed? How these fossils fuels were made?

Question 3
Why is Tungsten used almost exclusively for filament of electric lamps?

Question 4
Fill in the blanks
(i)The major constituent of the Biogas ___________
(ii)Which of these gaseous fuel has higher calorific value (a) hydrogen (b) Methane (c) LPG (d) Biogas ____________
(iii) two gases, other than carbon-dioxide that are given out during burning of fossil fuels and contribute towards acid rain formation_________

Question 5
How is nuclear energy generated? Explain the process of producing electricity with Nuclear energy?  Mention the major hazard of it

Question 6
Why Charcoal is better fuel than coal?

Question 7
What are the good characteristics of a good fuel?

Question 8
True and False Statements
(a) Acid rains happens because  burning of fossil fuels release oxides of carbon, nitrogen and sulphur in the atmosphere.
(b) Ocean thermal energy is due to pressure difference at different level
(c) Sun is the ultimate source of energy
(d) Methane is  not a constituent of biogas
(e) The potential energy of the high altitude wind is the source of wind power
(f) Charcoal  and coal are both fossil fuels

• Notes
• NCERT Solutions
• Assignments

### Practice Question

Question 1 Which among the following is not a base?
A) NaOH
B) $NH_4OH$
C) $C_2H_5OH$
D) KOH
Question 2 What is the minimum resistance which can be made using five resistors each of 1/2 Ohm?
A) 1/10 Ohm
B) 1/25 ohm
C) 10 ohm
D) 2 ohm
Question 3 Which of the following statement is incorrect? ?
A) For every hormone there is a gene
B) For production of every enzyme there is a gene
C) For every molecule of fat there is a gene
D) For every protein there is a gene

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