Show the formation of image by a concave mirror using a candle and a screen.
Show Hint
If the candle is placed within the focal length (u<f), no image will be formed on the screen because the image is virtual. You would need to look into the mirror to see the virtual, erect, and magnified image.
Step 1: Understanding the Concept:
A concave mirror is a converging mirror. It can form a real, inverted image of an object placed in front of it, provided the object is placed beyond the focal point (F). This real image can be projected onto a screen. The size and location of the image depend on the object's distance from the mirror. Step 2: Apparatus Required:
- A concave mirror with a holder
- A candle (as the object)
- A white screen
- A meter scale or optical bench Step 3: Ray Diagram and Procedure: Ray Diagram (Object between C and F):Procedure:
1. Find Rough Focal Length: First, find the approximate focal length (f) of the mirror by focusing the image of a distant object (like a window) onto the screen. The distance from the mirror to the screen is roughly f. The center of curvature (C) is at 2f.
2. Setup: Place the concave mirror in its holder. Place the lit candle in front of it.
3. Case 1 (Object beyond C): Place the candle at a distance greater than 2f from the mirror. Place the screen between C and F and move it to get a sharp image.
4. Case 2 (Object at C): Place the candle at 2f. Move the screen to get a sharp image.
5. Case 3 (Object between C and F): Place the candle between f and 2f. Move the screen beyond C to get a sharp image. Step 4: Observation:
- Case 1 (Object beyond C): A real, inverted, and diminished (smaller) image is formed on the screen between C and F.
- Case 2 (Object at C): A real, inverted image of the same size is formed at C.
- Case 3 (Object between C and F): A real, inverted, and magnified (larger) image is formed beyond C.
This demonstrates the different types of real images formed by a concave mirror.
