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The earth takes 24 h to rotate once about the axis. How much time does the Sun take to shift by 2°, when viewed from the earth?

Asked in GSEB Board March 2023 · Snell's law, slabs and apparent depth

Answer: (2) 480 s

Step-by-step solution

Given: 360° of apparent rotation in 24 h=86400 s.

Idea: the Sun's apparent shift is the earth's rotation, so time and angle are in direct proportion.

One degree: (86400)/(360)=240 s.

Two degrees take twice as long: 2×240.

So the Sun shifts by 2° in 480 s, that is 8 minutes.

Why the other options are wrong

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