What is Angle: Definition and 1000 Discussions

In Euclidean geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle.
Angles formed by two rays lie in the plane that contains the rays. Angles are also formed by the intersection of two planes. These are called dihedral angles. Two intersecting curves define also an angle, which is the angle of the tangents at the intersection point. For example, the spherical angle formed by two great circles on a sphere equals the dihedral angle between the planes containing the great circles.
Angle is also used to designate the measure of an angle or of a rotation. This measure is the ratio of the length of a circular arc to its radius. In the case of a geometric angle, the arc is centered at the vertex and delimited by the sides. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any other point and its image by the rotation.

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  1. J

    Power Electronics Rectifier Firing Angle and Overlap Angle

    Homework Statement Homework Equations Since question says the current is always continous, so overlap is always there. So option B is incorrect. Also since firing angle is increased from 0 to 45, the overlap angle will reduce. So it'll be less than 45. So option A is incorrect. The Attempt...
  2. Pushoam

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  3. I

    Dynamic contact angle simulation in COMSOL

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  4. R

    Projectile motion above ground given only angle and height

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  5. karush

    MHB 243.12.5.21 acute angle btw vectors

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  6. CAT 2

    The angle and distance of a projection - Grade 11 physics

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  7. CAT 2

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  8. C

    B How should I express this angle in words?

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  9. J

    Current Angle More Than Ninety Degrees

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  10. J

    How Much Work Is Done When Pulling a Sled at an Angle?

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  11. Z

    Interior and Exterior Angle of a Polygon: Formula not working

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  12. A

    I Is the Compton scattering angle related to the incident energy?

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  13. K

    B How do astronomers find the "parallax angle" of a star?

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  14. karush

    MHB Angle b/w Velocity $\&$ Acceleration Vectors at $t=0$

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  15. T

    B Eratosthenes angle measurement

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  16. N

    Linear polarizers: angle between the electric & magnetic fields

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  17. L

    MHB Formula for changing a plane intersection angle

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  18. Anonymous123451234

    How Is the Vertical Force Calculated at the Hinge in a Beam and Sign System?

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  19. P

    I Determining The Inclination Angle of A Stellar Binary System

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  20. A

    Elastic Collision Angle Proof

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  21. L

    Pulley at an Angle Problem - Newton Forces

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  22. ubergewehr273

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  23. R

    Intuition for why escape velocity doesn't depend on angle

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  24. A

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  25. S

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  26. E

    Projectile Motion: Determining Launch Angle

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  27. A

    How to calculate projectile off cliff when angle is below th

    Homework Statement Cliff is 50 m tall Stone thrown downwards with velocity of 12 m/s and 22 degrees below horizontal What is the time it will take to hit the ground? Homework Equations V=d/t D= Vi t + 1/2at^2The Attempt at a Solution Vx1= cos (22)(12) = +11.12620625 Vy1= sin (22) (12) =...
  28. A

    Finding the direction of an angle in the unit circle

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  29. patrykh18

    ∆KE if angle between force and displacement varies

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  30. C

    How Does Angle of Force Application Affect Acceleration on a Frictional Surface?

    Homework Statement A force is applied to an initially stationary block of mass 2.65 kg that sits on a horizontal floor as shown. The 81.0 N force is applied at θ = 50° angle to the vertical. The coefficients of friction between the floor and the block are μs = 0.895 and μk = 0.665. What is the...
  31. O

    Pulling an object at an angle with friction -- find the Kinetic Energy

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  32. A

    I Angle of projection for maximum range

    Hi, I can't seem to work out how angle of projection for maximum range comes out to be (pi/4 - Beta/2) This happens when the projectile is protected up the inclined plane. Similarly, I couldn't understand how the angle comes out to be (pi/4 + Beta/2) when the projectile is protected down the...
  33. N

    Conduction Angle of a Diode Circuit

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  34. A

    Elastic collision and angle of deflection problem

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  35. S

    Coulomb's Law, Three Charges, X Y Components, Angle

    Homework Statement This is finding net force on Q3. I was taught by my Physics teacher to always get angle from the Positive side of x-axis (+X-Axis). For example in the above situation, if the angle is -30deg from the +x-axis (assuming the Q3 is the origin), Why is F31 x-component = 140...
  36. O

    Projection at an angle - throwing stones

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  37. X

    How convert a point on an X and Y grid to a angle degree?

    <Moderator's note: Moved from a technical forum and thus no template.> Hello Forum, This post is a spin-off from this post: https://www.physicsforums.com/threads/how-much-would-time-pass-between-watching-the-sun-set.925257/#post-5840279 If I have an X and Y point on a grid that represents...
  38. F

    Projectile Motion: Angle & Range with Air Resistance and Wind

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  39. S

    Find angle between displacement and velocity vector

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  40. alphaj

    Organic chem: draw this in line angle structure

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  41. A

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  42. M

    What is the angle and displacement of the plane?

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  43. jlmccart03

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  44. C

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  45. F

    Induction motor - calculating rotor flux angle

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  46. F

    What is the Maximum Angle of Deflection in a Particle Collision?

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  47. Q

    Plane wave angle of incidence calculation

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  48. H

    The force required to raise a bridge/lever to an angle?

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  49. E

    Angle between a Point on a Ellipse and its Center

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  50. Z

    Angle between 2 charged spheres hanging from string

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