Chapter 11
1 What are transparent materials?
2 Name some natural sources of light
Give some examples of arti cial sources of light
What is a shadow?
De ne translucent materials.
Mention a property of light. The property of light is to travel in straight line,
Name the type of object known to block the light.
What happens when a ray of light falls on the mirror?
Give an example of a pin hole Camera.
Name the type of re ection that helps us to see most things.
Part-B
What is light? Name the di erent sources of the light alongwith examples.
Name some important phenomena related to light.
What does a shadow show?
Write any two important characteristics of a shadow.
Di erentiate between the luminous and non luminous object. Give examples.
1. Fill in the blanks:
2. i. The sun is a _______ source of light.
ii. Light is a form of ______.
iii. A shadow is ________ in color.
iv. Candles, oil lamps and earthen lamps are _______ sources of light.
v. An image has the _______ of the object.
vi. A highly polished furniture acts like a ______.
2. True/False:
i. Any non-luminous body can be made luminous by heating it.
ii. Any material through which light energy pass partially or wholly is called an opaque object.
iii. A cardboard is an example of an opaque object.
iv. A glass is a transparent object.
v. A shadow is colorful.
3. What is light?
4. Is moon a luminous or non-luminous body?
5. How does light travel?
6. Write one property of light.
7. Name one living thing which emits light?
8. What could be the shape of the shadows?
9. Does the color of opaque object a ect the color of the shadow?
10. When shadow cannot be formed?
11. Does the ame of gas stove emit light? Explain.
12. Can light pass through opaque objects?
13. Can we see shadow even if there is no light?
14. What is the color of a shadow?
15. How can non-luminous object be made luminous?
16. Why does a pinhole camera produces an inverted (upside down) image?
17. What do you understand by rectilinear propagation of light?
18. When we are able to see the object?
ii. 19. What is a re ector? Give one example.
20. Why polished surfaces causes glare in our eyes?
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Chapter 12
List any two insulators.
Name any two conductors.
Name the device that helps in breaking a circuit.
How many terminals does an electric cell has?
De ne electric current.
What do you understand by a closed circuit?
What type of current is generated by dry cell?
What is an open circuit?
Why is pure water a bad conductor of electricity?
How is electricity generated in a dry cell?
SECTION B
11. Identify the gure below. What is its function?
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What is a switch? How does it regulate the ow of electric current?
What do you mean by electric circuit? What are the different types of circuits?
The closed path of ow of electric current is called electric circuit.
Name any four home appliances used that work on electricity
Why are conductors and Insulators both important for us?
What is lament?
Q1. Fill in the blanks.
i. —————————do not allow current to pass through them.
ii. Air is an——————
iii. Our body is a ——————conductor of electricity.
iv. The metal cap is the —————- terminal of the electric cell.
Q2. True/False
i. Impure water can also conduct electricity.
ii. An electric cell produces electricity from the chemicals stored inside
it.
iii. The metal disc is the positive terminal.
iv. Brass is a conductor.
v. Insulators allow current to pass through them.
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