Midterm Review: Optics and Telescopes

Question 1

What are the three primary purposes/functions of a telescope?

Answer 1

Light gathering, resolution, and magnification

Question 2

What’s the difference between reflecting and refracting telescopes?

Answer 2

Refracting telescopes use convex lenses bend light toward a focal point, while reflecting telescopes use concave mirrors to re-direct light

Question 3

How do you calculate the magnification of a telescope?

Answer 3

M = ft/fe

Question 4

How does a telescope brighten an image?

Answer 4

The bigger the diameter, the more light will be collected

Question 5

What is the “Aperture” of a telescope? How would increasing it affect images?

Answer 5

Aperture is the lens/mirror diameter, increasing it would allow more light to be collected and brighter images

Question 6

What is the “exposure time” of a camera? What effect would increasing it have on the final image?

Answer 6

Exposure time is how long the camera will be exposed to light photons. Increasing it would make images brighter and more blurry