They are not necessarily positive. If you're talking about scientific/mathematical calculations of time, then only half are positive ;).
If you are talking about how we in america culturally refer to time in day to day speech and thought, I think that's a question having to do not with time itself, but with the society that refers to it as important only when perceiving it in one direction; forward. (subjectively, of course, compared to other, older, societies around the world)
In many other cultures when telling time in day to day speech it is common to say "H minus mm" or "without mm, H" as would be closer to a direct translation. Those would be considered a negative interval, moving backwards, while telling time.
To better answer your question, I would need clarification on what you mean.
Yes, but most of the time we use intervals of 1.
The positive regions of a function are those intervals where the function is above the x-axis. It is where the y-values are positive (not zero). The negative regions of a function are those intervals where the function is below the x-axis. It is where the y-values are negative (not zero).
Time interval is the period of time between the start and end of an activity.
No the second is broken down into smaller intervals of time.
No
Yes, but most of the time we use intervals of 1.
30 second intervals
The order of the geologic time intervals is Eon, Era, Period, Epoch.
The positive regions of a function are those intervals where the function is above the x-axis. It is where the y-values are positive (not zero). The negative regions of a function are those intervals where the function is below the x-axis. It is where the y-values are negative (not zero).
Geologists have divided Earth's history into a series of time intervals. These time intervals are not equal in length like the hours in a day. Instead the time intervals are variable in length. This is because geologic time is divided using significant events in the history of the Earth.
The shortest is Planck time.
Intervals are a space or a period of time between things. Regular intervals would be a period of time between things that is always constant; the time stays the same(:
Degrees longitude. The intervals divided this way are the time zones.
Time interval is the period of time between the start and end of an activity.
Time! A change between two points in time is the interval, sometimes referred to in engineering terms "delta."-InThree21
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if there unequal velocities in equal intervals of time.