Premium practical diagram for focal length of a concave mirror.
Why this practical matters
These experiments use rays, lenses, mirrors, refraction, and diffraction to measure light behavior.
Measure from the pole of the mirror and use a clear, sharp image on the screen.
What You Need
Apparatus
- ray box or laser
- screen
- lenses, mirrors, glass block, or diffraction grating
- metre rule and protractor
- concave mirror and screen
Key Formula
1/f = 1/u + 1/v
Say the formula out loud before you start the calculation. It helps students and examiners follow your logic.
How To Do It
- Set up the focal length of a concave mirror apparatus neatly and make sure the scale or meter reading starts from a known point.
- Align the ray carefully, mark the normal, take readings from the correct reference point, and use sharp images or clear fringe patterns.
- Use the result to explain the physics idea in simple English. Measure from the pole of the mirror and use a clear, sharp image on the screen.
Simple Explanation
Measure from the pole of the mirror and use a clear, sharp image on the screen.
In the lab, we are not just collecting numbers. We are showing a physics rule in a real and reliable way. That is why careful setup, repeat readings, and clear labelling matter so much.
Common Mistakes
- Measuring from the wrong point on a lens or mirror.
- Not drawing the normal.
- Letting the image blur before reading the scale.
Exam Tips
- Mention angle of incidence and angle of refraction correctly.
- Keep the ray box narrow and bright.
- Write the formula that matches the experiment.
- State the observation, the method, and the conclusion in that order.
Simulator / Quick Check
Focal Length of a Concave Mirror simulator
Enter values and press Run.