One half of a convex lens is covered with black paper. Will this lens produce a complete image of the object? Explain your observations.
When one-half of a convex lens is covered with a black paper, this lens produces a complete image of the object. To prove it we perform an experiment as given below:
Take a convex lens and cover half part of it by using a black paper. Place it vertically in a stand. On one side of it place a burning candle. On opposite side of the lens fix a white screen. Adjust the position of candle or screen till clear image of burning candle is formed on the screen. We observe that the image is a complete image of the object (burning candle).
From the experimental observations, we find that image formation does not depent upon the size of a lens. A smaller lens can also form complete image of an object placed in front of it. However, brightness of the image decreases when some part of lens is blocked. It is because now lesser number of rays pass through the lens.
