One degree of longitude corresponds to how much difference in time?
- A.One minute
- B.Four minutes
- C.Fifteen minutes
- D.One hour
Correct answer
Explanation
The correct answer is B, four minutes. The earth completes one rotation of 360 degrees in 24 hours, that is 1,440 minutes, and dividing 1,440 by 360 gives four minutes for every degree of longitude.
Option C, fifteen minutes, reverses the relationship that candidates most often remember, which is that the earth turns fifteen degrees in one hour; fifteen is the number of degrees, not of minutes. Option D, one hour, is the time for fifteen degrees, not for one. Option A, one minute, would mean a full rotation in six hours, which is plainly wrong. Every numerical question in this chapter rests on this single conversion, so keep both forms ready: one degree equals four minutes, and fifteen degrees equal one hour. The half degree that appears in Indian Standard Time therefore accounts for exactly two minutes.
Read the full article: Latitudes, Longitudes and Time: Grid, IST and Date Line
Practice Questions
View allIndian Standard Time is based on which meridian?
- A.75 degrees east
- B.82 degrees 30 minutes east
- C.88 degrees 30 minutes east
- D.90 degrees east
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This meridian passes near Mirzapur in Uttar Pradesh and runs roughly through the middle of the country, so it was adopted as the standard meridian of India.
Read the full explanation →The Tropic of Cancer does not pass through which of the following Indian states?
- A.Jharkhand
- B.Chhattisgarh
- C.Odisha
- D.Tripura
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The Tropic of Cancer passes through eight states, namely Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram.
Read the full explanation →Which is the only parallel of latitude that is a great circle?
- A.The equator
- B.The Tropic of Cancer
- C.The Arctic Circle
- D.The Tropic of Capricorn
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A great circle is one whose plane passes through the centre of the sphere and which therefore divides it into two equal halves.
Read the full explanation →The Prime Meridian passes through which place?
- A.Paris
- B.Greenwich
- C.Rome
- D.Washington
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The meridian running through it was accepted as the zero meridian, from which all longitudes are counted east and west, and its local time is Greenwich Mean Time, the reference for the world's standard times.
Read the full explanation →The Arctic Circle is drawn at which latitude?
- A.23.5 degrees north
- B.45 degrees north
- C.66.5 degrees north
- D.90 degrees north
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The Arctic Circle marks the latitude beyond which the sun stays above the horizon for the whole of at least one day in midsummer and below it for the whole of at least one day in midwinter, the phenomenon known as the midnight sun and the polar night.
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