Explain the construction and working of a pinhole camera

CBSE Class 6 CBSE Class 6 Science
1

Explain the construction and working of a pinhole camera.

2
  • Take an ordinary hollow rectangular cardboard box with a small hole in the middle of one face of the box.
  • The size of the hole should be equal to the pinhead of a common pin.
  • Remove the opposite face of the box and fix a wax paper in its place with the help of a thread or a rubber band.
  • The box is blacken from inside so that any light which falls on its walls directly or indirectly is absorbed.
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    Working of a pinhole camera
  • Place a luminous object such as a burning wick (XY) of the candle in front of the pinhole, an inverted picture X’Y’ of the wick is obtained on the wax paper. This picture is called the image .
  • The image obtained is inverted.
  • Such an image is formed because the light travels in a straight path. Hence, light from the upper point X of the wick passes through the pinhole and strikes the wax paper at X’.
    Similarly, light from the lower point Y of the wick passes through the pinhole and strikes the wax paper (or screen) at Y’.
  • When light from all other points between X and Y passes through the pinhole they strike the wax paper in between X’ and Y’. Hence, an inverted image is formed on the wax paper.
    image