Light sources worksheet - Free Printable

Problem Analysis:

The task involves identifying which of the given objects are light sources and then ranking them based on their brightness. Let's break it down step by step.

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Step 1: Identify Light Sources

A light source is an object that emits its own light. Objects that reflect light (like mirrors) or do not emit light at all (like curtains) are not considered light sources.

#### Objects Listed:
1. Lamp: A lamp emits light when turned on, so it is a light source.
2. Torch: A torch emits light when activated, so it is a light source.
3. Mirror: A mirror reflects light but does not emit its own light, so it is not a light source.
4. Curtain: Curtains do not emit light; they block or reflect light, so they are not a light source.
5. Sun: The Sun is a natural light source that emits its own light, so it is a light source.
6. Moon: The Moon does not emit its own light; it reflects sunlight, so it is not a light source.
7. Candle: A candle emits light when lit, so it is a light source.
8. Eyes: Eyes do not emit light; they detect light, so they are not a light source.

#### Light Sources Identified:
- Lamp
- Torch
- Sun
- Candle

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Step 2: Rank the Light Sources by Brightness

Now, we need to rank the identified light sources from brightest to least bright.

1. Sun: The Sun is the brightest natural light source, emitting an immense amount of light.
2. Torch: A torch is very bright, especially in dark conditions, but it is not as bright as the Sun.
3. Lamp: A lamp is quite bright, depending on its type (e.g., incandescent, LED), but it is generally less bright than a torch.
4. Candle: A candle emits the least amount of light among these options.

#### Ranking:
- Brightest: Sun
- Very bright: Torch
- Quite bright: Lamp
- Least bright: Candle

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Final Answer:

1. Light Sources: Lamp, Torch, Sun, Candle
2. Ranking by Brightness:
- Brightest: Sun
- Very bright: Torch
- Quite bright: Lamp
- Least bright: Candle

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\boxed{\text{Sun, Torch, Lamp, Candle}}
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