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 = 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.

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

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 × (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 = (1/2)³ = 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