General Science - MCQ Practice Questions

Escape velocity is mathematically derived as v = √(2GM/R), where G is gravitational constant, M is the planet's mass, and R is its radius.

These two properties directly determine the gravitational field strength at the planet's surface, which defines the minimum velocity needed to escape gravitational attraction.

~343 m/s at 20°C.

Power P = 1/f (in meters). P = $\frac{1}{0}$.15 = 6.67 Diopters (positive for converging lens)

The mirror equation relates object distance, image distance, and focal length to locate where an image forms in a concave mirror.

Step 1: [Identify Given Values]

For this concave mirror problem, we extract the known measurements from the question.

Step 2: [Apply Mirror Equation]

The mirror equation relates these three quantities and allows us to solve for the unknown image distance.

Substituting the values:

Since v is positive, the image forms in front of the mirror (on the same side as the object).

The image is formed 15 cm in front of the mirror. Answer: (B)

Using transformer equation Vs/Vp = Ns/Np, we get Vs = 220 × ($\frac{100}{500}$) = 44 V

The force on a current-carrying conductor in a magnetic field is called the Lorentz force, given by F = BIL

After 3 half-lives (30 years), the fraction remaining = ($\frac{1}{2}$)³ = $\frac{1}{8}$

In elastic collisions, both momentum and kinetic energy are conserved

Young's modulus Y = Stress/Strain = (F/A)/(ΔL/L), a measure of material stiffness

When object is between lens and focus (u < f), a convex lens produces virtual, erect, magnified image

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

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

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

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

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

Work by gravity W = -mgh (negative because displacement is opposite to force direction). W = -5 × 10 × 10 = -500 J.

For parallel connection: 1/R = $\frac{1}{6}$ + $\frac{1}{3}$ + $\frac{1}{2}$ = $\frac{1}{6}$ + $\frac{2}{6}$ + $\frac{3}{6}$ = $\frac{6}{6}$ = 1. Therefore R = 1Ω.

Ferromagnetism is the property of materials like iron, cobalt, and nickel to retain permanent magnetic properties due to aligned electron spins.

De Broglie proposed that all matter exhibits wave-particle duality. Both light (photons) and electrons show properties of both waves and particles, confirmed by experiments like double-slit interference and photoelectric effect.

Work done against constant pressure: W = -PΔV. Given W = -500 J and P = 2 atm = 2 × 101325 Pa. ΔV = -W/P = 500/(2 × 101325) ≈ 2.47 × 10⁻³ m³ = 2.47 L.