Explanation

• A plane mirror produces a virtual image, meaning it's not a real image that can be projected onto a screen.
• The image is also upright, meaning it's not inverted or flipped.

Explanation

Copper, silver, aluminum, gold, steel, and brass are common conductors of electricity.

The most highly conductive metals are silver, copper, and gold

Silver is the first-best conductor of heat.

Copper is the second-best conductor of heat.

Explanation

The theory of relativity usually encompasses two interrelated theories by Albert Einstein:

They were proposed and published in 1905 and 1915

E =mc2

C in this equation, the velocity of light

Explanation

• Clouds float in the atmosphere because they are less dense than the surrounding air. Clouds are formed when water vapor in the air condenses into visible liquid droplets or ice crystals. These droplets or crystals are suspended in the air, and because they are less dense than the air, they float.
• The density of a cloud is typically around 0.05-0.5 g/m³, which is much less than the density of air, which is around 1.2 g/m³. This density difference allows clouds to remain suspended in the air, even though they are heavier than air in terms of their mass.

Explanation

Refraction is the bending of light as it passes from one medium to another (e.g., air to water).

This occurs due to a change in the speed of light in different media.

Explanation

• The Earth takes approximately 23 hours, 56 minutes, and 4 seconds to complete one rotation on its axis, which is called a sidereal day.
• This is the time it takes for the Earth to rotate once relative to the fixed stars.
• The extra 4 minutes is due to the Earth's slightly ellipsoidal shape and the effects of the Moon's gravitational pull.

Explanation

Bernoulli’s Principle explains that faster airflow over the wings creates lower pressure, producing lift that keeps the airplane in the air.

Explanation

When air increases, more molecules exert force on the surface.

This greater force causes atmospheric pressure to rise.

Explanation

Parsec (per sec) is an astronomical unit used to measure large distances between stars or galaxies.

1 parsec ≈ 3.26 light years.

Explanation

Power = Force • Velocity (dot product),  

This gives instantaneous power, measuring how much work is done per unit time.