Explanation

The pressure of a gas in a container is affected by:

• Temperature (increases with temperature)
• Volume (decreases with increasing volume)
• Density of gas (increases with density)

However, the material of the container does not directly affect the pressure of the gas.

Explanation

• Red stars, also known as red dwarfs, typically have a surface temperature around 3000°C (5400°F).
• This is the coolest temperature range for stars, and it's what gives them their distinctive red color.

Explanation

• Dolphins have a wide audible range that is adapted to their aquatic environment.
• They can hear sounds in the range of 20 Hz to 120,000 Hz, which is far beyond the human audible range.

Explanation

• Security mirrors are typically convex mirrors.

The examples of concave mirrors:

• Cosmetic mirrors (makeup mirrors)
• Dentist mirrors
• Car headlight mirrors

Explanation

• A Kaleidoscope is an optical instrument that uses mirrors and glass fragments.
• It used to create multiple images of an object, creating a colorful and symmetrical pattern.

Explanation

• Uranus is an extremely cold planet and it's called Ice Giant.
• It's identical to the planet Neptune.
• It has 27 moons.
• It's largest moon; Titania.

Explanation

• Opaque objects do not allow any light to travel through them, as they absorb or reflect all of the light.
• Examples: Metals, wood, stone, paper, books, table, wall, newspaper, brick wall, wooden objects, trees and thick clothing.

Explanation

Force can change an object's:

• Direction (by changing its trajectory)
• Size (by compressing or expanding it)
• Speed (by accelerating or decelerating it)

But force cannot change an object's mass.

Mass is a fundamental property of an object that remains constant, regardless of the forces acting upon it.

Explanation

• High-speed electrons from particle detectors are used to determine the diameter of atomic nuclei through techniques such as electron scattering or electron microscopy.
• By measuring the scattering pattern or the diffraction pattern of the electrons, researchers can infer the size and shape of the atomic nucleus, including its diameter.

Explanation

• The resistance of a filament lamp increases at higher voltages.
• The increase in voltage leads to an increase in current, which heats up the filament and increases the resistance.
• The increased temperature causes the atoms in the filament to vibrate more, making it more difficult for electrons to pass through and increasing the resistance.