what are the various sources of light used at home? find out the way of minimizing the dependence on artificial light and maximising the use of natural light
Answers
Explanation:
2. Light, Shadows and Reflections
I. Choose the correct answer:
1.Which of these objects can cast a shadow?
a.A Lighted bulb b. A Wooden door c.A glass pane d. None of them
2. What would be the colour of the shadow of a red ball?
a. Black b. Red c. Blue. d. None of these
3.Which of these are required to form the shadow of a ball?
a. Torch b. Ball c. Screen d. All of these
4. You will see the shortest shadow of yourself in sunlight
a. In the morning b. At noon c. In the evening d. In the night
5. A plane mirror forms an image of an object because __________ it light from the object
a. Absorbs b. Reflects c. Passes d. None of these
II. Write true or false:
1. During an eclipse the sun moon and earth are in a straight line.
2.Reflection is responsible for the formation of a shadow
3. Pure water can reflect light.
4. A solar eclipse is seen on a full moon day.
5.We cannot see a luminous object in a dark room.
III. Match the following:
1. Frosted glass-reflection
2. Beam of light-formed when an object blocks light
3. Image-translucent material
4. Shadow-bunch of rays
5. Lunar eclipse-full moon day
6. Solar eclipse- New moon day
IV. Answer the following:
1. What is rectilinear propagation of light give an example from your daily life observation to prove rectilinear propagation of light
2. Describe an activity to show that light travels in a straight line
3. Write down the differences between a shadow and an image.
4. What is pinhole camera? How does it works explain in detail with principle?
5. Paul set up an experiment as shown in the diagram here
Which of the following will make the shadow of an object bigger
a. The object is moved closer to the screen
b. The torch is moved closer to the object
c. The object is moved further away from the screen
i.a & b only ii.b & c only iii.a & c only d. All of the above.
6. What is mean by reflection of light?
7. What are the various sources of light used in home find out ways of minimising the dependence on artificial light and maximizing the natural light.
8. Find out about Thomas Edison and his invention of electric bulb .Write an essay on his life and contributions.