universe & solar system section 4 MCQ Questions & Answers Detailed Explanation

Answer: (b)

Answer: (a)

The North and South poles have either no night for around six months of the year during summer, or complete night for six months of the year during winter.

This is because, during summer, the sun is basically permanently above the horizon for half of the year, due to the tilt of the earth on its axis. If the earth were positioned upright with the poles in a vertical position, then the North and South Poles would have daytime and night time separated by light and darkness, just like the rest of the planet.

However, because it is tilted and rotates around the sun's energy for six months one pole or the other has to always be in the shadow.

Answer: (c)

Earth is called the ‘Blue Planet’ due to the abundant water on its surface. This is because liquid water covers most of the surface of the planet. The Earth has the right mass, chemical composition, and location can support liquid water.

Answer: (d)

The eclipse of the Sun occurs when the Moon comes between Sun and the Earth. The Moon orbits the Earth once a month, and eclipses happen if it lines up exactly with the Earth and the Sun. Solar eclipses occur at New Moon when the Moon is between Earth and the Sun.

Lunar eclipses occur at Full Moon when Earth is between the Sun and the Moon. Eclipses do not take place every month because the orbits of the Moon and Earth are tilted at an angle. Most of the time, the line-up is not precise enough for an eclipse.

Answer: (b)

White Dwarf is known as Fossil star. They are supported by electron degeneracy pressure. It amplifies the contrast with red giants.

They are both very hot and very small. They are the opposite of black holes. They are the end-products of small, low-mass stars.

Answer: (d)

Stalagmite is a onical mineral deposit, usually calcite or aragonite, built up on the floor of a cavern,formed from the dripping of mineral-rich water.