UPSC Civil Services
General Science

Insulin, produced by the pancreas, lowers blood glucose by facilitating glucose uptake into cells. Glucagon raises blood glucose levels.

Elastic potential energy U = ½kx². U = ½ × 100 × (0.2)² = 50 × 0.04 = 2 J.

Refractive index n = c/v. Therefore, v = c/n = (3 × 10⁸)/1.5 = 2 × 10⁸ m/s.

Chlorine (Cl) has atomic number 17, with electronic configuration 2, 8, 7 (K-shell: 2, L-shell: 8, M-shell: 7).

First convert 72 km/h = 20 m/s. Using v = u + at: 0 = 20 + a(8), so a = -20/8 = -2.5 m/s². Magnitude of deceleration is 2.5 m/s².

Pure water at 25°C has a pH of 7, which is neutral. This is because [H⁺] = [OH⁻] = 10⁻⁷ M, making pH = -log(10⁻⁷) = 7.

Photosynthesis is the process where plants use sunlight, water, and CO₂ to produce glucose and oxygen. The equation is 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂.

Using v = u + gt, where u = 0 (at rest), t = 2s, g = 10 m/s². Therefore v = 0 + 10 × 2 = 20 m/s.

1 amu = 1.66054 × 10⁻²⁷ kg. This is used to express atomic and molecular masses.

Newton's Law of Universal Gravitation states F = G(m₁m₂)/r². This is the fundamental law describing gravitational attraction between masses.