To make a Telescope
Telescopes are used to view distant objects with a larger angular magnification. An important aspect of telescope is resolution for which one needs a convex lens of large aperture as the objective. Here we make a very simple telescope to give the feel and excitement.
A concave lens of focal length 5 cm, a convex lens of focal length 20 cm and same radius, a transparency sheet, double sticky tape, cellophane tape.
- Put the transparency sheet on a horizontal surface, peel off a length of the double sticky tape (15 cm) and stick it on the transparency sheet. The length should be slightly more than the perimeter of the lenses.
- Now stick another piece of tape of same length, parallel to the first piece at a separation of exactly 15 cm (20cm - 5cm). Remove the upper non sticky cover to expose the sticky surface.
- Carefully put one of the lenses on a tape in vertical orientation and the other lens on the other tape parallel to the first one.
- Now roll the sheet very carefully, keeping the two lenses parallel to each other. After one complete roll, use cellophane tape to securely fix up the roll.
- The telescope is ready. Keeping the concave lens towards eye, look at distant objects and enjoy. Write your experience with this telescope.
Figure to be made