Explanation

• Comets are small celestial bodies mainly composed of ice, dust, and rocky material.
• They travel around the Sun in highly elliptical or elongated orbits.
• Halley’s Comet, which returns approximately every 76 years.

Additional information:

• Asteroids: Mainly rocky or metallic bodies.
• Meteoroids: Small pieces of rock or metal moving through space.

Last verified on 05-10-2026

Explanation

• Rear view mirrors in vehicles are convex mirrors.
• They give a wider field of view.
• Images formed are virtual, upright, and smaller.
• This helps drivers see more traffic behind them.
• It is a curved mirror that bulges outward.
• It is commonly used in side mirrors of cars, buses, and motorcycles.

Last verified 26-04-2026

Explanation

• Ole Rømer was the first person to experimentally demonstrate that light has a finite speed in 1676.
• He used observations of Jupiter’s moon Io to estimate the speed of light.

Additional information:

• The modern accepted speed of light in vacuum is 299,792,458 m/s.

Last verified on 07-10-2026

Explanation

• Jupiter has the fastest rotation of all planets.
• It completing one rotation in about 9 hours 56 minutes.

Additional information:

• Venus has the slowest rotation.
• It taking about 243 Earth days.
• Earth: ~24 hours
• Mars: ~24 hours 37 minutes.

Last verified on 06-10-2026

Explanation

• The correct mathematical form is V = IR.
• Here V = voltage, I = current, R = resistance.
• Ohm’s law states that current is directly proportional to voltage when temperature is constant.
• It describes the relationship between voltage, current, and resistance.

Last verified on 12-04-2026