Question

if it is 8 p.m. on 12th May at Prime Meridian write the dates and time of 150 degree east and 120 degree West​

Answer 1

$\huge\mathfrak\green{AnsWer:-}$

Since the earth makes one complete revolution of 360° in 24 hours, that means it passes through 15° in one hour, that also means 1° in 4 minutes.

As you must know Earth rotates from west to east, so every 15° we go eastwards local time is advanced by 1 hour.

Likewise, if you go westwards, local time is retarded by 1 hour.

So, we can conclude that places east of Greenwich gain time as they see sun earlier, whereas places west of Greenwich see the sun later and lose time.

So, if we know GMT, to find local time, we merely have to add or subtract the difference in the number of hours from given longitude.

(Longitude is angular distance which is measured in degrees along the equator east or west of Prime meridian) to cut in short,basically these are vertical lines which pass through both poles.