Solar Cooker

Q.

Why is the sun called the ultimate source of energy?

Q.

Which type of mirror is used in a solar furnace and support your answer.

Q.

(a) With the help of a labelled diagram, explain the construction and working of a solar cooker.
(b) Why is the solar cooker box painted black from inside ?
(c) Why is the solar cooker box covered with a glass sheet ?

Q.

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

Q.

Explain the construction and working of a box type solar cooker.

Q.

What is the surface that is a good absorber of radiation?

Q.

how does a concave mirror help in Solar cooking

Q.

------------- energy is the main driving force of the ecological system

1. Solar

2. Mechanical

3. Hydro

4. Electric

Q. Why is the copper tube of a solar water heater painted black from outside?

Q. What is the range of temperature which can be achieved in a box-type solar cooker in two to three hours ?

Q.

Which part of the solar cooker is responsible for green house effect in it?

1. Coating with black colour inside the box

2. Mirror

3. Glass sheet

4. Outer cover of the solar cooker

Q.

What are the limitations in harnessing wind energy?

Q.

In order to make an efficient solar cooker, the cover of cooker box should be made of :
(a) transparent plastic sheet (b) shining aluminium sheet
(c) butter paper sheet (d) transparent glass sheet

Q.

Which type of mirror is used as a reflector in a box-type solar cooker

1. plane

2. concave

3. parabolic

4. none of the above

Q.

Which part of the solar cooker is responsible for the greenhouse effect?

1. Coating with black color inside the box

2. Mirror

3. Glass sheet

4. The outer cover of the solar cooker

Q. What type of reflector is used in a box-type solar cooker?

Q. Question 8 (c)
Name the type of mirror used in the given situation.
Solar furnace
Support your answer with reason.

Q.

How to you define reflecting power of a body?

Q.

What are the disadvantages of solar power?

Q. What is estimation of solar constant?

1. 1.4 kW per square meter
2. 1.6 kW per square meter
3. 1.4 W per square meter
4. 1.4 kW per square centimeter

Q.

''When parallel sunrays are incident on concave mirror it converges...meet at focus and hence the solar cooker works'', but sun rays are not parallel at all so how can we say this??

Q. Name two devices which can be utilised for the cooking of food so as to save fuel.

Q. (a) Name that part of a box-type solar cooker which allows the sun's heat rays to enter the box but does not allow inside heat to go out.
(b) Explain why, a plane mirror reflector is used in a box-type solar cooker.

Q. A solar cooker may not cook food if :
(a) the solar cooker is not placed in the shade (b) the glass sheet cover of solar cooker is not closed
(c) a convex mirror reflector is not used (d) the food containers of insulating material are not used

Q. The part of box-type solar cooker which is responsible for producing greenhouse effect is :
(a) plane mirror reflector (b) black coating inside the box
(c) glass sheet cover (d) utensils placed in the cooker box

Q.

A solar cooker will be the means of cooking food in the future. Give a reason for the same.

Q.

Sun is the primary source of wind energy.

1. wind

2. sun

Q.

Question 24
How can solar energy be harnessed? Mention any two limitations in using solar energy. How can we overcome these limitations?

Q.

How are high temperatures achieved in solar cookers?

1. none of these.

2. mirrors are used to reflect sunlight on the the cooker thus more heat.

3. mirrors absorb more sunlight falling on the cooker thus more heat.

4. mirrors diffuse light in all direction.

Q.

Explain the construction and working of a solar cooker with a neat diagram.