Telescope worksheet - Free Printable

Let’s go step by step to fill in the table correctly.

We are comparing Refracting Telescopes and Reflecting Telescopes.

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Step 1: Definition

Look at the two definition boxes:

- “An optical instrument that uses 2 convex lenses to collect and focus light from far away objects.” → This is for Refracting Telescope, because it uses lenses (refraction).

- “An optical instrument that uses 2 mirrors and a lens to collect and focus light from far away objects.” → This is for Reflecting Telescope, because it uses mirrors (reflection) + sometimes a lens in eyepiece.

✔ So:
- Refracting: uses 2 convex lenses
- Reflecting: uses 2 mirrors and a lens

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Step 2: Diagram

There are two diagrams labeled A and B.

- Diagram A shows: Primary Mirror, Secondary Mirror, Light bouncing off mirrors → this is Reflecting Telescope

- Diagram B shows: Objective Lens, Eyepiece Lens, Light going through lenses → this is Refracting Telescope

✔ So:
- Refracting → Diagram B
- Reflecting → Diagram A

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Step 3: Process

How does each telescope work?

- In refracting telescopes: Light rays pass through lenses → they bend (refract) and converge.

- In reflecting telescopes: Light rays hit mirrors → they bounce (reflect) and converge.

From the options:

- “Light rays are refracted and they converge.” → Refracting

- “Light rays are reflected and they converge.” → Reflecting

✔ So:
- Refracting: Light rays are refracted and they converge.
- Reflecting: Light rays are reflected and they converge.

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Step 4: Advantage

What’s good about each?

Options:

- “They collect more light and give clearer images.” → This is true for Reflecting Telescopes — big mirrors can be made larger than lenses, so they gather more light.

- “Lenses are more durable than mirrors.” → Actually, this is misleading. Mirrors can be coated and protected; lenses can scratch or have chromatic aberration. But among given choices, we must pick what fits best.

Wait — let’s think again.

Actually, one advantage of refracting telescopes is that their tubes are sealed, so less dust gets in, and lenses don’t need recoating like mirrors. But the option says “Lenses are more durable than mirrors” — which is not really accurate scientifically, but since it’s the only other option left, and it’s paired with refracting...

But wait — look again at the advantages listed:

Option 1: “They collect more light and give clearer images.” → Better for large telescopes → Reflecting

Option 2: “Lenses are more durable than mirrors.” → Maybe meant as an advantage for refracting? Even if not perfectly accurate, in context of worksheet, likely assigned to refracting.

BUT — actually, standard science knowledge:

✔ Real advantage of reflecting telescopes: Can make very large mirrors → collect more light → better for faint objects.

✔ Real advantage of refracting telescopes: No central obstruction (like secondary mirror), sharper contrast, sealed tube.

But since our options are limited, and one says “collect more light” → definitely reflecting.

The other says “lenses are more durable” — perhaps intended for refracting, even if debatable.

So we’ll assign:

- Refracting: Lenses are more durable than mirrors. (as per given options)
- Reflecting: They collect more light and give clearer images.

*(Note: In reality, modern large telescopes are mostly reflectors because mirrors can be supported from behind and made much bigger. But for this worksheet, we follow the given options.)*

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Now let’s compile everything into the table.

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Final Answer:

| Points of comparison | Refracting Telescope | Reflecting Telescope |
|----------------------|-----------------------------------------------|------------------------------------------------|
| Definition | An optical instrument that uses 2 convex lenses to collect and focus light from far away objects. | An optical instrument that uses 2 mirrors and a lens to collect and focus light from far away objects. |
| Diagram | Diagram B | Diagram A |
| Process | Light rays are refracted and they converge. | Light rays are reflected and they converge. |
| Advantage | Lenses are more durable than mirrors. | They collect more light and give clearer images. |