One-half of a convex lens is covered with black paper. Will this lens produce a complete image of the object? Verify your answer experimentally. Explain your observations.

Yes, it will produce a complete image of the object. However, the intensity or brightness of the image will be reduced.

Experiment : To show that a half-covered convex lens can produce a complete image of the object.

Apparatus needed : A convex lens, a candle, and two black sheets of paper.

Procedure :

1. Place a convex lens on the table. Light a candle with a match stick and place it near one side of the lens on the table (turn off the lights of the room in order to get dark).

2. Take the sheet of paper and place it on the other side of the lens as the candle.

3. Now focus the image formed on the sheet of paper by moving the sheet only.

4. Observe the image carefully.

5. Mark the positions of candle, lens and screen.

6. Now, turn off the light. Take the convex lens and cover half of it with the second sheet of black paper.

7. Mount the lens on the table in the original position and repeat the above experiment.

Observations : A complete image of the object is obtained in both the cases. However, the image formed with half of the convex lens covered is less bright.

Conclusion : The half covered lens will also produce a complete image of the object. However, the image formed will be less bright.