Indian 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
Correct answer
Explanation
The correct answer is B, 82 degrees 30 minutes east. 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. Its local time, which is five hours and thirty minutes ahead of Greenwich Mean Time, is kept as Indian Standard Time everywhere from Gujarat to Arunachal Pradesh.
Option A, 75 degrees east, passes through the western part of the country and is often offered because it sounds like a round figure. Option C, 88 degrees 30 minutes east, lies close to Kolkata, which once kept its own local time before standardisation. Option D, 90 degrees east, is the standard meridian used by Bangladesh, six hours ahead of Greenwich. The half hour in the Indian offset comes directly from the thirty minutes in the chosen meridian, since half a degree equals two minutes of time.
Read the full article: Latitudes, Longitudes and Time: Grid, IST and Date Line
Practice Questions
View allOne degree of longitude corresponds to how much difference in time?
- A.One minute
- B.Four minutes
- C.Fifteen minutes
- D.One hour
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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.
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.
Read the full explanation →