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.

Explanation

Bohr's quantum condition states that the angular momentum of an electron in a circular orbit is quantized:

mvr = nh / 2π

where m is the mass of the electron,

v is the velocity,

r is the radius of the orbit,

n is the principal quantum number,

and h is Planck's constant.

Explanation

The momentum 

𝑝 of a photon is given by the equation:

𝑝=ℎ/𝜆 

where:

h is Planck's constant,

λ is the wavelength of the photon.

Since photons are massless, their momentum is not related to mass but to their wavelength.

Explanation

An electron volt (eV) is a unit of energy.

It is defined as the amount of kinetic energy gained or lost by a single electron when it is accelerated through an electric potential difference of one volt.

Specifically:

1eV=1.602×10 −19 Joules

Thus, the electron volt is a convenient unit for measuring small amounts of energy, particularly in the fields of atomic and particle physics.

Explanation

• Alternating Current (AC) is the flow of electric charge that periodically changes direction.
• This type of current is commonly used in power distribution systems and household electrical outlets.