Question

At any given time, different parts of the earth experience different seasons. Apart from the earth’s revolution around the sun, which of these is the reason for this?
A. The earth’s rotation
B. The elliptical shape of the earth’s orbit
C. The presence of the moon
D. The tilt of the earth’s axis of rotation

Answer 1

Hint: Earth's rotation is the rotation of planet Earth around its own axis. Earth rotates eastward, in prograde motion. As viewed from the north pole star Polaris, Earth turns counterclockwise.

Complete answer: Looking at the above options:
Option a: The earth’s rotation causes day and night. This option is incorrect.
Option b: When the Earth's orbit is more elliptical, the planet spends more time away from the sun, and the Earth gets less sunlight throughout the year. This option is incorrect.
Option c: The moon's gravitational pull on the Earth is the main cause of the rise and fall of ocean tides. This option is incorrect.
Option d: The tilt of the earth's axis of rotation causes seasons when Earth's axis is tilted at an angle of about 23.4 degrees and different parts of Earth receive more solar energy than others. Because of Earth's axial tilt , our planet orbits the Sun on a slant which means different areas of Earth point toward or away from the Sun at different times of the year. Around the June solstice, the North Pole is tilted toward the Sun and the Northern Hemisphere gets more of the Sun's direct rays. This is why June, July and August are summer months in the Northern Hemisphere. At the same time, the Southern Hemisphere points away from the Sun, creating winter during the months of June, July and August. Summer in the Southern Hemisphere is in December, January, and February, when the South Pole is tilted toward the Sun and the Northern Hemisphere is tilted away. This option is correct.

Hence, the correct answer is option 'd'.

Note: The period of revolution of the Earth around the Sun is equal to one year. The Earth makes one revolution on its axis in about 24 hours.