Explanation

1. The frequency ($f$) of a wave is inversely proportional to its wavelength ($\lambda$) when the wave speed ($v$) is constant.

2. The fundamental wave equation is:

   $$\mathrm{<font\; color="\#0000ff"><b>v</b></font>}<font\; color="\#0000ff"><b>=</b></font>\mathrm{<font\; color="\#0000ff"><b>f</b></font>}\mathrm{<font\; color="\#0000ff"><b>\lambda </b></font>}$$

   where:

   • $v$ = wave speed (m/s),

   • $f$ = frequency (Hz),

   • $\lambda$ = wavelength (m).

3. This applies to all types of waves (e.g., sound, light).

Explanation

Vertical columns in the periodic table are called groups.

Horizontal rows are called periods.

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

1 meter (m) = 1000 millimeters (mm)

1 meter (m) = 100 centimeters (cm)

1 centimeter (cm) = 10 millimeters (mm)

1 millimeter (mm) = 0.1 centimeters (cm)

1 kilometer (km) = 1000 meters (m)

Explanation

A spectrometer is an instrument used to measure the properties of light over a specific portion of the electromagnetic spectrum, especially to analyze line spectra produced by atoms or molecules.

It helps identify elements or compounds by detecting their unique emission or absorption lines in the spectrum.

A spectrometer is an instrument used to measure the wavelength of light (or other electromagnetic radiation) by dispersing it into a spectrum.

It is commonly used to analyze the spectral lines of elements, which correspond to specific wavelengths.

Explanation

1. The formula for kinetic energy is $KE=\frac{1}{2}m{v}^2$, where:

   • $m$ is the mass of the body,

   • $v$ is the velocity of the body.

2. Thus, kinetic energy is proportional to:

   • Mass of the body (directly proportional),

   • Square of the velocity of the body (proportional to $v^2$).

Explanation

Right-Hand Rule: When current flows through a straight wire, the magnetic field lines form concentric circles around the wire.

The direction of these circular field lines depends on the current direction (given by the right-hand rule: thumb points in current direction, fingers curl in field direction).

Explanation

Radioactivity is the process where an unstable atomic nucleus emits radiation (such as alpha, beta, or gamma rays) to become more stable.

It is a nuclear process, as it involves changes within the nucleus itself.

Explanation

The induced current will flow in such a direction so as to oppose the cause that produces it is the statement of Lenz's Law.

This law reflects the principle of conservation of energy in electromagnetic induction.

Explanation

Isotopes are atoms of the same element (same number of protons/nuclear charge) but different masses (different number of neutrons).