Which one of the following is the longest parallel of latitude?
- (a)Tropic of Cancer
- (b)Tropic of Capricorn
- (c)Arctic Circle
- (d)Equator
Correct — D, the Equator. Parallels of latitude are circles drawn parallel to the Equator; their circumference shrinks steadily from the Equator (0°, about 40,075 km) towards each pole, where a parallel finally becomes a point. The Equator is therefore the longest parallel of latitude, and the only parallel that is a great circle. The Tropics of Cancer and Capricorn (23.5°) and the Arctic Circle (66.5°) all lie closer to a pole and so trace shorter circles.
- (a)Tropic of Cancer — At 23.5° N it lies well away from the Equator, so its circle is shorter than the Equator's.
- (b)Tropic of Capricorn — At 23.5° S it is the same length as the Tropic of Cancer, but still shorter than the Equator.
- (c)Arctic Circle — At 66.5° N it lies far closer to the North Pole, making it one of the shortest of the named parallels.
Parallels of latitude are imaginary east–west circles measured in degrees north or south of the Equator. Because the Earth is a sphere, these circles are largest at the Equator and grow smaller towards the poles. The Equator alone is a 'great circle' (its plane passes through the Earth's centre); every other parallel is a 'small circle'.
Rank the options by how far each lies from the Equator: the closer to a pole, the shorter the circle. The Equator, at 0°, is nearest the Earth's widest girth and so is the longest.
- The Equator (0° latitude) is about 40,075 km long — the longest parallel.
- Parallels decrease in length from the Equator towards the poles.
- The Equator is the only parallel that is a great circle.
- The Tropics lie at 23.5°, the Arctic and Antarctic Circles at 66.5°.
- Assuming a higher-latitude circle could be longer — it is always shorter.
- Mixing up parallels (unequal) with meridians of longitude (all equal in length).
Asked as the 'longest parallel/latitude' — the answer is the Equator (0°), the only parallel that is a great circle.
No directly related past PYQ was found.
- practice — not a real PYQ
Which one of the following circles of latitude is a great circle?
- (a)Tropic of Cancer
- (b)Equator
- (c)Arctic Circle
- (d)Antarctic Circle
Answer(b) Equator — its plane passes through the Earth's centre, so it is the only parallel that is a great circle.
- practice — not a real PYQ
As latitude increases from the Equator towards the poles, the length of a parallel of latitude
- (a)increases
- (b)stays the same
- (c)decreases
- (d)first increases, then decreases
Answer(c) decreases — the circles get smaller until a pole becomes a point.