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# Telling time (unlabeled clock)

CCSS.Math:

Sal tells time on unlabeled analog clocks. Created by Sal Khan.

## Want to join the conversation?

- where doses the clock show 6 as 30 minuts or half an hour?(10 votes)
- It's called duality. I can get a piece of string and I can say "This string is this long" and I can add a weight to the end of the string and let the weight sit on the floor while I hold the other end up and I can say, "This is the distance between my hand and the floor"...

There is 60 minutes in an hour.... or one full revolution of the minute hand on the clock face, but half a revolution is half an hour, and it's half way around the clock face, at the six.. It's basically thinking two things from the same event.(1 vote)

- how much time is there in 5 or 6 weeks?(8 votes)
- Well 24 x 7=168 so then add that 5 times 168+168+168+168+168=840 hours(9 votes)

- If the hour hand goes around the circle twice, would this be calculated as one day?(4 votes)
- There is 24 hours in one day. 12 hours in night and 12 hours in day. People think its not true only because of their timetable. They could sleep for 9 hours and be awake for 15 hours. Thats a good question.(7 votes)

- Never mind I don't need help anymore.(5 votes)
- Hey sis I can answer your question about why we see the moon when it is daytime.. We see the moon when it is daytime because the sun's light reflect from the moon's surface. This is why we see the moon when it is daytime.(4 votes)

- Is it smarter idea to learn time on a digital watch before an analog watch that tells you the time?(4 votes)
- I agree. It is good to be able to tell time the harder way.(5 votes)

- Is there a formula for adding hours to military time?(5 votes)
- The A.M. hours are all before12:00pm. You right it from 0000-12:00. When you write times smaller than that you write it with a zero in front of it (0900 =9:00) or (1000 =10:00). All hours after12:00pm are created by adding 1 hour onto it (1:00pm = 1300) (10:00pm = 2200).

Hope this helps!(5 votes)

- Does time depend on the position of the sun towards Earth?(5 votes)
- Im not sure if this may correctly answer you're question,but let's give it a go,shall we?

You see,space and time is a single dimension.3D+1D=4Dimensions.For example,the sun creates a warp in space-time.This warp keeps the planets in motion.If the sun however disappeared,the earth would not fall out of orbit immediately.Istead,the light comming from the sun would take 8 minutes to reach earth.At precisely that time,the earth would fall out of orbit.Same goes for the other planets.(3 votes)

- why didn,t you put zero in front of four(3 votes)
- 043 and 43 are the exact same number, so we don't put the 0 in front because...

A) it's not needed

B) it takes up unnecessary space

C) it makes the number more complicated(2 votes)

- why do we need A.M. and P.M.?(2 votes)
- They stand for Ante Meridiem and Post Meridiem. Those two terms mean "before noon" and "after noon", respectively.(3 votes)

- When we write time dose the mins come first(0 votes)
- The order is hours, minutes, and seconds. Usually just hours and minutes are used.(14 votes)

## Video transcript

We're asked, what time is it? So first, we want to look at the
hour hand, which is the shorter hand, and see where
it is pointing. So this right over
here would have been 12 o'clock, 1 o'clock, 2
o'clock, 3 o'clock, 4 o'clock. And it looks like it's a
little bit past 4 o'clock. So we are in the fourth hour. So the hour is 4. And then we have to
think about the minutes. The minutes are the longer hand,
and every one of these lines represent 5 minutes. We start here. This is 0 minutes past the hour,
then 5 minutes past the hour, then 10 minutes past the hour. So the time is-- the minutes are
10, 10 minutes past the hour, and the hour is 4, or it's 4:10. Let's do a few more. What time is it? So first, we want to
look at the hour hand. That's the shorter
hand right over here. It's at-- let's see. This is 12, 1, 2,
3, 4, 5, 6, 7, 8, 9. And it's between 9 and 10. It's just past 9. So it's still in the ninth hour. It hasn't gotten to
the 10th hour yet. The ninth hour's from starting
with 9 all the way until it's right almost before
it gets to 10, and then it gets
to the 10th hour. So the hour is 9, and
then we want the minutes. Well, we can just
count from 0 starting at the top of the clock. So 0, 5, 10, 15, 20, 25, 30. It's 9:30. And that also might
make sense to you, because we know there are
60 minutes in an hour. And this is exactly
halfway around the clock. And so half of 60 is 30. Let's do one more. What time is it? So let's count. This is 12, 1-- actually,
we can even count backwards. We can go 12, 11, 10. So right now we're
in the 10th hour. The hour hand has passed 10,
but it hasn't gotten to 11 yet. So we are in the 10th hour. And how many minutes
past the hour are we? So this would be 0, 5, 10,
15, 20 minutes past the hour. That's where the longer
hand is pointing. It is 10:20.