Explanation

Sound waves are characterized by amplitude (loudness), wavelength (distance between wave peaks), and frequency (pitch).

These parameters help describe how sound behaves and is perceived.

Explanation

The standard meter and kilogram are made from an alloy of platinum and iridium to ensure durability and accuracy.

This alloy is used because it resists corrosion and retains its shape over time, crucial for precise measurement.

Explanation

A screw gauge (micrometer) measures very small lengths with high precision, up to 0.01 mm.

It is commonly used to measure wire thickness and small objects accurately.

Explanation

The wrist is made up of eight small bones called carpals.

These bones provide flexibility and movement to the wrist joint.

Metacarpals are found in the palm.

Metatarsals are in the foot.

Explanation

The refractive index (n) is defined as:

n = Speed of light in air / Speed of light in medium

Given:

n = 1.5

Speed of light in air = 3 × 10⁸ m/s

Rearrange the formula to solve for Speed of light in glass:

Speed of light in glass = Speed of light in air / n

= (3 × 10⁸ m/s) / 1.5

= 2 × 10⁸ m/s

Explanation

Alkali metals (like sodium and potassium) react vigorously with air and water, often catching fire.

To prevent this, they are stored in oil (like paraffin oil) to keep them stable and unreactive.

Explanation

Crossing over occurs during meiosis, where genetic material is exchanged between homologous chromosomes.

This process produces recombinant chromatids, which carry a new combination of genes.

Explanation

Polar orbiting satellites travel over the Earth from pole to pole and are mainly used for collecting weather and climate data.

They provide detailed global coverage, useful for forecasting and environmental monitoring.

Explanation

The bright side of the Moon is the part that reflects sunlight and is visible from Earth.

This side changes shape during phases of the Moon.

Explanation

Boiling a magnet (especially in water) does not generate enough heat to affect its magnetic properties.

In contrast, hammering, heating, or dropping disturb the alignment of magnetic domains, leading to demagnetization.