how fast does the date line move? If it's midnight in London, how many minutes later is Bristol?

Answer 1

It doesn't move at all. The fictional date line is in the same place it has been.

If London and Bristol are in the same time zone, there is NO difference in time. It is because of this "minutes off" reasoning that time zones were established. If you are in GMT time, and so is Bristol, there is no difference in time. That way all the tube schedules are synchronized.

However, I know London goes on Daylight Savings Time in the summer, I do not know if Bristol does, in which case, they would be right off by 60 minutes.

Answer 2

Pedantic answer: none, because all clocks in Britain are set to UTC in the winter, UTC+1h in the summer.

Serious answer: All the way around the world = 360 degrees = 24 hours = 1440 minutes time difference. So 1 degree = 4 minutes time difference.

The junction of the Birmingham New Street and London Paddington lines in Bristol Temple Meads railway station is at longitude 2.575 degrees West of the Greenwich meridian (which runs through London .....), so sunrise in Bristol (over Temple Meads station) will occur 10.3 minutes = 10 min 18 sec. after sunrise in London (over the Greenwich meridian).