Light from the Moon takes about how much time to reach the Earth?
- A.1.3 seconds
- B.8 minutes 20 seconds
- C.27.3 days
- D.1 hour
Correct answer
Explanation
The correct answer is A, 1.3 seconds. The Moon is on average about 384,400 kilometres from the Earth. Light covers about three lakh kilometres in a second, so it crosses that distance in a little over a second. This is the standard figure asked in one-line questions about the Moon, along with its distance.
Option B, eight minutes and twenty seconds, is the time sunlight takes to reach us, and the two figures are deliberately placed together in such questions. Option C, 27.3 days, is the period the Moon takes both to rotate once on its axis and to revolve once around the Earth; because the two are equal, the same face of the Moon is always turned towards us. Option D is far too long and matches nothing in the Earth and Moon system.
Read the full article: Solar System and the Earth: Planets, Moon and Motions
Practice Questions
View allWhich is the hottest planet of the solar system?
- A.Mercury
- B.Venus
- C.Mars
- D.Jupiter
Show answer
Venus is wrapped in a very thick atmosphere of carbon dioxide, which lets sunlight in but does not let the heat escape.
Read the full explanation →Approximately how long does sunlight take to reach the Earth?
- A.8 minutes 20 seconds
- B.1.3 seconds
- C.4.2 years
- D.24 hours
Show answer
The Sun is about 149.6 million kilometres from the Earth, a distance called one astronomical unit, and light travels about three lakh kilometres in a second.
Read the full explanation →Which is the largest planet of the solar system?
- A.Saturn
- B.Neptune
- C.Jupiter
- D.Uranus
Show answer
Jupiter is the fifth planet from the Sun and the largest of all by both diameter and mass; it is a gas giant of hydrogen and helium.
Read the full explanation →Apart from Uranus, which planet rotates on its axis from east to west, that is in a direction opposite to most planets?
- A.Mercury
- B.Venus
- C.Mars
- D.Saturn
Show answer
Almost every planet, the Earth included, rotates from west to east, which is why the Sun appears to rise in the east.
Read the full explanation →The occurrence of seasons on the Earth is caused mainly by which of the following?
- A.The changing distance between the Earth and the Sun
- B.The rotation of the Earth on its axis
- C.The tilt of the Earth's axis along with its revolution around the Sun
- D.The gravitational pull of the Moon
Show answer
The axis of the Earth is tilted about 23.5 degrees from the vertical and keeps pointing in the same direction throughout the year.
Read the full explanation →