Telescopes

We were given class time to finish the Thin-Lens Practise Problems. Here are the answers:

1. di= 36cm hi= -3.6cm
2. di= -15cm hi= 2.5cm
3. a)di= 510cm b)hi= -62.5
4. di= -30cm hi= 1.8cm
5. di=do= 5.0cm
6. di= -14cm f=4.7cm

The class was then given an assignment from the textbook; read pages 396-399, write two paragraphs summarizing telescopes and one type of telescope and draw the diagrams for each type of telesscope.
Telescopes
To view distant objects such the moon and stars with detail, two or more lenses must be used together. The images are smaller but since they are much closer they appear larger.
Galilean Telescope

This telecope uses both converging and diverging lenses. The image produced is virtual, upright and larger.
Reflecting Telescope
Refracting Telescope

This telescope uses two converging lenses. The image produced is virtual, inverted and larger.
Terrestrial Telescope
This telescope uses three converging lenses, the third lens located in the middle (erector lens) has the purpose of inverting the image so it is upright like the object. Images produced are virtual, upright and larger.
The next blog writer will be anybody who has not written and sits by the windows of the classroom