How long is from am to pm?

Answer 1

Midnight to noon is 12 hours (AM), noon to midnight is another 12 hours (PM). Therefore, it is 12 hours from PM to AM.

Answer 2

It can be as long as 11hours 59 minutes or just 1 minute.

You can have

11:59 am

One minute later is

12 noon ( NOT 12 am/pm)

one minute later it is

12:01 pm.

Or you can

11:59 am

12 hours later later is

11: 59 pm ( one minute to 12 midnight)

one minute later it is

12 midnight

one minute later it is

12:01 am

'am/pm' are the initials of the Latin phrases 'ante/post meridian' , which means 'before/after noon'.