9.1 Telescopes

• What are telescopes used to observe?

  Distant objects in the sky
• What is an advantage of refracting telescopes?

  Simple design
• What is a disadvantage of reflecting telescopes?

  More complex design
• Order the steps in light focusing for a refracting telescope:

  1️⃣ Light enters through the lens

  2️⃣ Lens bends the light

  3️⃣ Light is focused
• Reflecting telescopes can be made larger than refracting telescopes.


  True
• Refracting telescopes are more expensive than reflecting telescopes.

  False
• What do reflecting telescopes use to reflect and focus light?

  Mirrors
• Reflecting telescopes do not suffer from chromatic aberration.
• What is the primary purpose of the objective lens in a refracting telescope?

  Focus light
• What does the eyepiece lens in a refracting telescope determine?

  Magnification
• What is the focal point in a refracting telescope?

  Light convergence
• Where is the objective lens located in a refracting telescope?

  Front
• The secondary mirror in a reflecting telescope is a convex mirror.
• The focal length in a reflecting telescope determines its magnifying power.


  True
• In a reflecting telescope, the focal point is located behind the primary mirror.
• Reflecting telescopes do not suffer from chromatic aberration.


  True
• One advantage of reflecting telescopes is the absence of chromatic aberration
• What are telescopes used to observe in the sky?

  Distant objects
• Refracting telescopes can be made as large as reflecting telescopes.

  False
• Match the property with the correct type of telescope:

  Light Focusing ↔️ Mirrors

  Chromatic Aberration ↔️ Present
• Which type of telescope is free from chromatic aberration?

  Reflecting
• Refracting telescopes can be made larger than reflecting telescopes.

  False
• What is the primary function of the objective lens in a refracting telescope?

  Collect and bend light
• What does the eyepiece lens in a refracting telescope do?

  Focuses light and magnifies
• The focal length of a refracting telescope determines its magnifying power.
• Reflecting telescopes use a secondary mirror to direct light to the eyepiece.


  True
• What is the focal point in a reflecting telescope?

  Where light rays converge
• The focal point in a reflecting telescope is where the light rays converge after reflecting off the primary mirror
• What is the primary function of the primary mirror in a reflecting telescope?

  Collects and reflects light
• The focal point in a reflecting telescope forms a real image


  True
• In a refracting telescope, light is focused by an objective lens
• Steps of light reflection in a reflecting telescope

  1️⃣ Light enters the telescope

  2️⃣ Light reflects off the primary mirror

  3️⃣ Light reflects off the secondary mirror

  4️⃣ Light passes through the eyepiece
• The formula for calculating the magnification of a telescope is M = f_objective / f_eyepiece


  True
• A longer focal length objective lens in a telescope increases its magnification
• What is diffraction, and how does it affect the resolving power of a telescope?

  Reduces resolving power
• Refracting telescopes are better suited for planetary imaging due to their simple design and lack of optical aberrations


  True
• Refracting telescopes are less prone to optical aberrations than reflecting telescopes when imaging planets.


  True
• Which type of telescope does not suffer from chromatic aberration?

  Reflecting telescopes
• Telescopes are instruments used to observe distant objects in the sky.

  True
• Refracting telescopes use lenses to bend and focus light