Explanation

• Asteroids are irregularly shaped solid objects composed primarily of rocks and metals.
• They are found mainly in the asteroid belt between Mars and Jupiter.

Explanation

• When sound waves reach the ear drum, it vibrates and causes the small bones (ossicles) behind the eardrum to vibrate.
• These vibrations are then transmitted to the liquid in the inner ear (cochlea).
• Where they are detected by small hairs (hair cells) and converted into electrical signals that are sent to the brain via the auditory nerve.

Explanation

• Terrestrial planets are small, rocky planets that orbit close to the Sun, and include Mercury, Venus, Earth, and Mars.
• They are composed primarily of silicate rocks and metals, and have surfaces that are heavily cratered.

Explanation

• A four-level laser is a type of laser that has four energy levels involved in the lasing process.
• The He-Ne laser (Helium-Neon laser) is a common example of a four-level laser.
• It works by exciting helium atoms, which then transfer their energy to neon atoms, causing them to emit laser light.

Explanation

A concave lens causes light rays to diverge or spread apart after passing through it.

That's why it’s also called a diverging lens.

Explanation

The speed of light traveling through a vacuum is exactly 299,792,458 meters (983,571,056 feet) per second. That's about 186,282 miles per second.

A universal constant is known in equations as "c," or light speed.

The speed of light in air is 2.9 × 10⁸ m/s.

Explanation

The absolute uncertainty in a measuring instrument is half of the smallest division (or the least count) of the instrument.

This value represents the potential error in a measurement due to the instrument's limitations. 

Explanation

 With a temperature rise, the velocity of sound increases.

This is because warmer temperatures cause molecules to move faster, allowing sound waves to propagate more quickly through the medium

Specifically, the speed of sound is directly proportional to the square root of the absolute temperature.

For every degree Celsius increase in temperature, the speed of sound in air increases by approximately 0.6 m/s

Explanation

Although the Balmer series mainly falls in the visible region, its limiting line (as $n\to \infty$) shifts into the UV region.

Explanation

Resistivity is a measure of how strongly a material opposes the flow of electric current.

Here's a general classification based on resistivity (in Ω-cm):

$10^5$ and 10 ^9 Ω-cm, it is classified as an insulator because it resists the flow of electric current very strongly.