What is Fall: Definition and 922 Discussions

Autumn, also known as fall in North American English, is one of the four temperate seasons. Outside the tropics, autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March (Southern Hemisphere), when the duration of daylight becomes noticeably shorter and the temperature cools considerably. Day length decreases and night length increases as the season progresses until the Winter Solstice in December (Northern Hemisphere) and June (Southern Hemisphere). One of its main features in temperate climates is the shedding of leaves from deciduous trees.
Some cultures regard the autumnal equinox as "mid-autumn", while others with a longer temperature lag treat the equinox as the start of autumn. In the English-speaking world, autumn traditionally began with Lammas Day and ended around Hallowe'en, the approximate mid-points between midsummer, the autumnal equinox, and midwinter. Meteorologists (and Australia and most of the temperate countries in the southern hemisphere) use a definition based on Gregorian calendar months, with autumn being September, October, and November in the northern hemisphere, and March, April, and May in the southern hemisphere.
In North America, autumn traditionally starts with the September equinox (21 to 24 September) and ends with the winter solstice (21 or 22 December). Popular culture in the United States associates Labor Day, the first Monday in September, as the end of summer and the start of autumn; certain summer traditions, such as wearing white, are discouraged after that date. As daytime and nighttime temperatures decrease, trees change colour and then shed their leaves. In traditional East Asian solar term, autumn starts on or around 8 August and ends on or about 7 November. In Ireland, the autumn months according to the national meteorological service, Met Éireann, are September, October and November. However, according to the Irish Calendar, which is based on ancient Gaelic traditions, autumn lasts throughout the months of August, September and October, or possibly a few days later, depending on tradition. In the Irish language, September is known as Meán Fómhair ("middle of autumn") and October as Deireadh Fómhair ("end of autumn"). Persians celebrate the beginning of the autumn as Mehregan to honor Mithra (Mehr).

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  1. M

    Me, Thinking About A Jump and A Fall

    Hi all. I had grade 11 physics so I know the basics on physics.. grade 12 comes later this year... Anyways I was thinking about the systems in a jump, and the motion involved and I know motion physics work and all so don't get me wrong :P I'm not trying to disporve something here... I just know...
  2. Q

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  3. T

    Free Fall Acceleration fractures Problem

    Homework Statement Falls resulting in hip fractures are a major cause of injury and even death to the elderly. Typically, the hip’s speed at impact is about 2.0 m/s. If this can be reduced to 1.3 m/s or less, the hip will usually not fracture. One way to do this is by wearing elastic hip pads...
  4. A

    Free Fall: Find Time & Height for Passing Balls

    A ball is thrown upward with speed V. At the instant the ball is thrown, second ball is dropped from rest at a height H above the thrown ball, but not directly above it. Ignore air resistance. How much time elapses before the balls pass each other? Find a value of H such that the ball thrown...
  5. H

    Calculating Free Fall: Water Balloon Question | Math Homework Help

    Homework Statement A student at a window on the second floor of a dorm sees his math professor walking on the sidewalk beside the building. He drops a water balloon from 18.0 m above the ground when the prof is 1.00 m from the point directly beneath the window. The professor is 170 cm tall...
  6. V

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  7. P

    Free Fall Kinematics Problem

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  8. K

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  9. G

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  10. rocomath

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  11. O

    The rise and fall of evidence-based natural philosophy.

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  13. I

    Read in a book that fall in a bh is the sameto go at c

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  14. A

    What speed will an object fall?

    I am looking for a formula to determine what speed an object will fall with a known height and weight. For example a 220 pound man falls from 65 ft, what speed will he be going when he hits the ground?
  15. N

    How Come Planets Don't Fall Into Stars?

    How come planets don't fall into stars as they orbit them? Einstein said a "space-time" curvature is caused because of the gigantic mass of the stars...why don't the planets orbiting these stars just fall right into them? Does it have something to do with the same reason why electrons never...
  16. S

    Going to RIT this Fall: Dual Majoring MicroE & Physics?

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  17. K

    Finding Initial Velocity and Direction of a Ball in Free Fall

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  18. S

    Radial Free Fall Proper Time

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  19. A

    Why Does the Acceleration of Free Fall Differ at the Equator?

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  20. L

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  21. B

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  22. B

    Does a Bird Immediately Fall When It Stops Flapping Its Wings?

    If a bird is in the air and for whatever reason it stops flapping it's wing, it'll fall back down. Is there a lag time between the stopping of the bird's wing and the fall? If there is, how long is it?
  23. T

    How far does the bucket fall?

    [SOLVED] How far does the bucket fall? Homework Statement A cylindrical pulley with a mass of M = 5.7 kg and a radius of r = 0.66 m is used to lower a bucket with a mass of m = 2 kg into a well. The bucket starts from rest and falls for 3.5 s. The acceleration of gravity is 9:8 m/s^2 ...
  24. T

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  25. L

    How Deep Is the Lake and What Is the Initial Velocity of the Ball?

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  26. L

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  27. K

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  28. M

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  29. rohanprabhu

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  30. M

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  31. S

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  32. E

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  33. T

    Why Electrons Don't Fall Into Nucleus of Atoms

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  34. G

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  35. T

    Calculating Maximum Velocity of a Dropped Object

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  36. H

    Is Free Fall Possible Without Air Resistance?

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  37. JasonJo

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  38. S

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  39. S

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  40. C

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  41. C

    How Do You Calculate Time and Distance in Free Fall Physics Problems?

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  42. clope023

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  43. M

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  44. R

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  45. P

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  46. J

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  47. S

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  48. W

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  49. P

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  50. O

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