General Science question from Panchayat Secretary (VLW) exam, 2025 by JKSSB
Which of the following power plants works on the principle of gravity?
Last updated Jun 9, 2026
Correct Answer:
Option B —
Hydro power
Hydroelectric power plants rely on the Earth's gravitational pull to generate electricity.
Water stored at a high elevation in a reservoir behind a dam possesses potential energy. When the floodgates open, gravity pulls the water downward through a pipe called a penstock. As the water rushes down, its potential energy converts into kinetic energy, which turns the blades of a turbine. The turbine then spins a generator to produce electricity.
Here is why the other options do not work on the principle of gravity:
Geothermal: Works on the principle of thermal energy generated and stored in the Earth's core (heat).
Solar power: Works on the photovoltaic effect or solar thermal concentration (light/radiant energy).
Nuclear power: Works on the principle of nuclear fission (splitting atomic nuclei to release thermal energy).
Answer verified by Quintessence Classes faculty — Karan Nagar, Srinagar.
