Biogas offers multiple benefits for rural India:
1. Clean cooking fuel: Reduces dependency on firewood, minimizing indoor pollution.
2. Energy source: Provides electricity and fuel for small-scale applications.
3. Waste management: Utilizes agricultural and animal waste, reducing environmental pollution.
4. Bio-fertilizer: The slurry left after biogas production is an excellent organic fertilizer.
5. Cost-effective: Reduces energy costs and promotes self-reliance.
| Case No. | Lens | Focal Length | Object Distance |
|---|---|---|---|
| 1 | \(A\) | 50 cm | 25 cm |
| 2 | B | 20 cm | 60 cm |
| 3 | C | 15 cm | 30 cm |