Variable Definition and 1000 Threads

A variable star is a star whose brightness as seen from Earth (its apparent magnitude) fluctuates.
This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as either:

Intrinsic variables, whose luminosity actually changes; for example, because the star periodically swells and shrinks.
Extrinsic variables, whose apparent changes in brightness are due to changes in the amount of their light that can reach Earth; for example, because the star has an orbiting companion that sometimes eclipses it.Many, possibly most, stars have at least some variation in luminosity: the energy output of our Sun, for example, varies by about 0.1% over an 11-year solar cycle.

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  1. A

    Mathematica How to use Switch with variable number of terms?

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  2. G

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  3. R

    B How Do Variables and Constants Differ in Mathematics?

    There are 2 things taught to us:variables(litersls ) and constants . If we let a value 'a' as a constant ,meaning it would remain unchanged and also it is a set of real numbers . If we take 'x' as a variable, meaning it can change and it is also a set of real nos. For ex. Lim (x>a) x = a...
  4. P

    Variable 100-350VAC output controlled by PLC?

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  5. Kaura

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  6. J

    Making a 12-24v DC variable power supply

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  7. G

    B Cepheid variable stars cause of light variance

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  8. D

    I Change of variable and Jacobians

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  9. Drako Amorim

    I Limit of a two variable function

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  10. L

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  11. Poetria

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  12. Arman777

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  13. kolleamm

    B Chain rule for variable exponents

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  14. HarrisC

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  15. mnb96

    I Equivalent definitions of random variable

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  16. E

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  17. Leo Freeman

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  18. K

    Work Kinetic energy using variable force

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  19. W

    I Variable displacement hydraulic pumps

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  20. cathal84

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  21. Rectifier

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  22. Z

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  23. Daquicker

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  24. Biker

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  25. bubblegumandcameras

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  26. B

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  27. R

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  28. P

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  29. L

    A Ortogonality of two variable functions

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  30. 1

    I Convert 2 variables into 1 representative variable

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  31. K

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  32. merricksdad

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  33. N

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  34. K

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  36. J

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  37. MeaningfromForm

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  38. Automata-Theory

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  39. victorhugo

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  40. Kernul

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  41. L

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  42. S

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  43. T

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  44. TheSodesa

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  45. C

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  46. E

    Variable Mass System: Calculate Speed of Truck

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  47. A

    B Calculating error when constant is divided by variable

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  48. P

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  49. KonaGorrila

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  50. W

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