Explanation

The speed of sound in water is approximately 1500 m/s, which is slower than in most solid materials but faster than in air.

This speed can vary slightly depending on factors like temperature and salinity.

Explanation

A star with an initial mass between 1 to 5 times the solar mass expands into a red giant and then collapses into a white dwarf.

A white dwarf is a dense, Earth-sized remnant of a star that has exhausted its nuclear fuel.

Explanation

Explanation

The product of frequency and time period is always equal to 1.

This is because frequency = 1/time period, so their product is 1.

Explanation

Helium hydride (HeH+) was the first molecule discovered in space, identified in 2019 by astronomers.

It was found in a planetary nebula, marking a significant discovery in molecular chemistry in space.

Explanation

Eduard Zirm performed the world's first successful human cornea transplant in 1905.

The operation restored vision to a man who had been blinded by a chemical burn.

Explanation

Rocket velocity is governed by the rocket equation, which depends on exhaust velocity and the rate of mass ejection.

Higher exhaust velocity and more mass loss (fuel ejection) produce greater thrust, resulting in higher rocket velocity.

Explanation

Iron is a magnetic material that can absorb and redirect magnetic field lines.

It shields precision instruments from external magnetic interference that could affect their accuracy.

Explanation

The speed of sound depends on the medium's density and elasticity.

It travels fastest in solids (due to tightly packed molecules) and slowest in gases (like air).

Glass (Solid) – ~5,640 m/s

Water (Liquid) – ~1,480 m/s

Wood (Solid) – ~3,300–3,600 m/s

Air (Gas) – ~343 m/s

Explanation

• A Periscope is an optical instrument used to observe objects that are not in direct line of sight.
• Such as monitoring the surface of the water from a submarine.