universe & solar system section 1 MCQ Questions & Answers Detailed Explanation

Answer: (c)

1. A prime meridian is a meridian (a line of longitude) in a geographical coordinate system at which longitude is defined to be 0°. A prime meridian and its opposite in a 360°-system, the 180th meridian (at 180° longitude), form a great circle. This great circle divides the sphere, e.g., the Earth, into two hemispheres.
2. The Tropic of Cancer also referred to as the Northern Tropic, is the most northerly circle of latitude on the Earth at which the Sun may appear directly overhead at its culmination.
3. The International Date Line (IDL) is an imaginary line of longitude on the Earth’s surface located at about 180 degrees east (or west) of the Greenwich Meridian.
4. Arctic Circle is an imaginary circle around the earth, parallel to the equator, at latitude66° 32' N; it marks the northernmost point at which the sun appears above the level of the horizon on the winter solstice.
5. Tropic of Capricorn is the parallel of latitude that is approximately $23 1/2$ degrees south of the equator and that is the southernmost latitude reached by the overhead sun 40.

Answer: (a)

The earth was nearly covered with snow and ice in pleistocene Era.

The Pleistocene is the geological epoch which lasted from about 2,588,000 to 11,700 years ago, spanning the world’s recent period of repeated glaciations.

Answer: (a)

The revolution of the earth around the sun alone is not enough for a change of seasons. Had the axis of the earth been vertical, the sun would have been vertical at the same latitude throughout the year.

Therefore the revolution of the earth and its inclination, both are necessary for the change of seasons.

Answer: (a)

Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material.

Comets show a perceptible growing tail, while asteroids do not.

Answer: (b)

Answer: (b)

One of the nicknames of Venus is “the Morning Star”. It is also known as the Evening Star.

Venus is called so because it appears brightest shortly before sunrise and shortly after sunset.