Everyday Science

A Geiger counter is an instrument used to detect and measure ionizing radiation, commonly referred to as radioactivity. It does not measure pressure or water flow.

Pure limestone is primarily composed of calcium carbonate (CaCO3), which is the main chemical constituent of limestone. Therefore, the correct answer is Calcium Carbonate.

Snow does not melt all at once because it requires a significant amount of energy to change from solid to liquid without a temperature change, due to its high latent heat of fusion. This means the snow absorbs heat while melting, preventing it from melting instantly.

Wireless transmission can be carried out using various types of electromagnetic waves including infrared waves, radio waves, and microwaves, making 'All of these' the correct answer.

From space, an astronaut sees the sky as black because there is no atmosphere to scatter sunlight and create the blue sky effect seen from Earth.

Galileo Galilei was the first to observe and document sunspots systematically using a telescope, making him credited with their discovery.

Venus is the only planet in our solar system that rotates clockwise (retrograde rotation) when viewed from above its north pole, unlike most other planets which rotate counterclockwise.

The concentration of carbon dioxide (CO2) in Earth's atmosphere is approximately 0.03 to 0.04%, which corresponds to about 300 to 400 parts per million (ppm). This makes option A the correct choice.

Uranus is often referred to as the 'Winter Planet' because of its extremely cold temperatures and its position far from the Sun, making it much colder than the other planets listed. Jupiter, while cold, is not typically called the Winter Planet.

The Aurora Borealis is commonly known as the Northern Lights because it occurs in the northern hemisphere near the Arctic Circle.