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The Earth takes 24 h to rotate once about its axis. The Sun will take ______ time to shift by 1° when viewed from the Earth.

Asked in GSEB Board August 2020 · Snell's law, slabs and apparent depth

Answer: (1) 240 s

Step-by-step solution

Given: one rotation, 360°, in 24 h=86400 s.

Idea: the Sun's march across the sky is the earth's own rotation seen from inside, so the time taken is proportional to the angle turned.

Time for one degree =(86400)/(360).

So the Sun takes 240 s — four minutes — to shift by 1°.

It is worth remembering: one degree of sky is four minutes of time.

Why the other options are wrong

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