In which among the following states in India, the Sun rays are never perpendicular? 1. Bihar 2. Chhattisgarh 3. Manipur 4. Rajasthan. Select the answer using the code given below:
- (a)1 and 2
- (b)1 and 3
- (c)2 and 3
- (d)2 and 4
Correct — B, 1 and 3 (Bihar and Manipur). The Sun's rays are perpendicular (directly overhead) only within the tropics — up to the Tropic of Cancer (about 23.5 degrees N) in India. A state can get overhead rays only if the Tropic of Cancer passes through it or lies to its south. Both Bihar and Manipur lie entirely north of the Tropic of Cancer, so the noon Sun is never directly overhead there. The Tropic of Cancer does pass through Chhattisgarh and through southern Rajasthan, so both of those DO receive perpendicular rays and are excluded.
- (a)1 and 2 — Chhattisgarh (2) is crossed by the Tropic of Cancer in its northern part, so it does get overhead Sun — it should be excluded, making this pair wrong.
- (c)2 and 3 — Chhattisgarh (2) receives perpendicular rays because the Tropic of Cancer passes through it; only Manipur (3) qualifies, so this pair is wrong.
- (d)2 and 4 — Both Chhattisgarh (2) and Rajasthan (4) are crossed by the Tropic of Cancer, so both DO get overhead Sun — this is the exact opposite of what the question asks.
The Sun is ever directly overhead only between the two Tropics, because its vertical noon rays migrate between 23.5 degrees N (Tropic of Cancer) and 23.5 degrees S (Tropic of Capricorn) over the year. In India the Tropic of Cancer is the northern limit — any place lying wholly north of it never sees the Sun perpendicular overhead.
Solve it by asking, for each state, whether the Tropic of Cancer passes through it (or south of it). The Tropic of Cancer crosses eight states; states lying entirely north of it (Bihar, Manipur, and also Punjab, Haryana, UP, etc.) never get overhead Sun. Chhattisgarh and Rajasthan are both crossed by the Tropic, so they are ruled out.
- The Sun is directly overhead only between the Tropics (23.5 N to 23.5 S); north of the Tropic of Cancer the noon rays are never vertical.
- The Tropic of Cancer passes through 8 Indian states: Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram.
- Bihar (roughly 24 N to 27.5 N) and Manipur (roughly 23.8 N to 25.7 N) lie entirely north of the Tropic of Cancer.
- Chhattisgarh (northern part) and southern Rajasthan (near Banswara) are crossed by the Tropic of Cancer, so parts of them do receive perpendicular rays.
Only Bihar (1) and Manipur (3) lie wholly north of the Tropic — hence the answer is (b).
- Picking states that are 'in the south' rather than checking the Tropic of Cancer.
- Forgetting that Chhattisgarh and Rajasthan are both crossed by the Tropic of Cancer.
- Assuming a state near the Tropic (but north of it) still gets overhead Sun.
Asked as which states the Tropic of Cancer crosses, or where the noon Sun can / cannot be overhead.
Among the following cities, which one is nearest to the Tropic of Cancer?
- (a) Delhi
- (b) Kolkata
- (c) Jodhpur
- (d) Nagpur
Answer(b) Kolkata
Same concept — the position of the Tropic of Cancer (about 23.5 N) relative to Indian places. Knowing which cities/states sit near or north of the Tropic is exactly what decides where the Sun can be overhead.
On 21st June, the Sun
- (a) does not set below the horizon at the Arctic Circle
- (b) does not set below the horizon at the Antarctic Circle
- (c) shines vertically overhead at noon on the Equator
- (d) shines vertically overhead at the Tropic of Capricorn
Answer(a) does not set below the horizon at the Arctic Circle
Same underlying idea — the overhead Sun on the June solstice reaches only the Tropic of Cancer, the very limit that determines the Indian states in which the Sun can (or can never) be perpendicular.
- practice — not a real PYQ
Through how many Indian states does the Tropic of Cancer pass?
- (a)Six
- (b)Seven
- (c)Eight
- (d)Nine
Answer(c) Eight — Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram.
- practice — not a real PYQ
In which of the following states is the noon Sun never directly overhead?
- (a)Madhya Pradesh
- (b)Gujarat
- (c)Uttar Pradesh
- (d)Jharkhand
Answer(c) Uttar Pradesh — it lies entirely north of the Tropic of Cancer (the other three are crossed by it).