Q1. Fill in the blanks.
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___________.
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. _________
Q3. What is light?
Q4. Is moon a luminous or non-luminous body?
Q5. How does light travel?
Q6. Write one property of light.
Q7. Name one living thing which emits light?
Q8. What could be the shape of the shadows?
Q9. Does the color of opaque object affect the color of the shadow?
Q10. When shadow cannot be formed?
Q11. Does the flame of gas stove emit light? Explain.
Q12. Can light pass through opaque objects?
Q13. Can we see shadow even if there is no light?
Q14. What is the color of a shadow?
Q15. How can non-luminous object be made luminous?
Q16. Why does a pinhole camera produces an inverted (upside down) image?
Q17. What do you understand by rectilinear propagation of light?
Q18. When we are able to see the object?
Q19. What is a reflector? Give one example.
Q20. Why polished surfaces causes glare in our eyes?
Q21. Write some natural sources of light.