Attempt all questions.

A $100-$watt bulb emits monochromatic light of wavelength $400nm.$ Calculate the energy of photons emitted per second by the bulb. Discuss the renewable energy systems: components, technical aspects, and environmental issues in detail.

Describe, with a neat sketch, the working of a hydrogen fuel cell and how does it work? And why it's dangerous?

How we produce electricity from wind energy? and what are the issues and challenges of wind energy?

How are Energy Sources Categorized? compare solar PV and Solar thermal energy with suitable diagrams.