What is Constant acceleration: Definition and 340 Discussions

In mechanics, acceleration is the rate of change of the velocity of an object with respect to time.
Accelerations are vector quantities (in that they have magnitude and direction). The orientation of an object's acceleration is given by the orientation of the net force acting on that object. The magnitude of an object's acceleration, as described by Newton's Second Law, is the combined effect of two causes:

the net balance of all external forces acting onto that object — magnitude is directly proportional to this net resulting force;
that object's mass, depending on the materials out of which it is made — magnitude is inversely proportional to the object's mass.The SI unit for acceleration is metre per second squared (m⋅s−2,






m

s

2







{\displaystyle {\tfrac {\operatorname {m} }{\operatorname {s} ^{2}}}}
).
For example, when a vehicle starts from a standstill (zero velocity, in an inertial frame of reference) and travels in a straight line at increasing speeds, it is accelerating in the direction of travel. If the vehicle turns, an acceleration occurs toward the new direction and changes its motion vector. The acceleration of the vehicle in its current direction of motion is called a linear (or tangential during circular motions) acceleration, the reaction to which the passengers on board experience as a force pushing them back into their seats. When changing direction, the effecting acceleration is called radial (or orthogonal during circular motions) acceleration, the reaction to which the passengers experience as a centrifugal force. If the speed of the vehicle decreases, this is an acceleration in the opposite direction and mathematically a negative, sometimes called deceleration, and passengers experience the reaction to deceleration as an inertial force pushing them forward. Such negative accelerations are often achieved by retrorocket burning in spacecraft. Both acceleration and deceleration are treated the same, they are both changes in velocity. Each of these accelerations (tangential, radial, deceleration) is felt by passengers until their relative (differential) velocity are neutralized in reference to the vehicle.

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  1. C

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    Im wondering if somebody can show me how to derive the five equations used to solve these types of problems. I've been unsuccesful in finding it on the net and am hoping someone on here can give me some insight. Thanks in advance.
  2. E

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  3. F

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  4. S

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  5. C

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    Ok, I've been running over this problem for about an hour now, and I can't figure out where I'm going wrong. I'm a complete newb, so I'm sure it's something stupid, but I could use the help. Homework Statement An object with an initial velocity undergoes constant acceleration. Position...
  6. H

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  7. T

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  8. I

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  9. F

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  10. M

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  11. D

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  12. D

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  13. D

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  14. M

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  15. ?

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  16. S

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    A proton has the acceleration a=CvxB, where a is the cross product of v and B (a,v,B are vectors). C is a constant and the magnetic field is constant. Prove that the magnitude of the v and a are constant. I know I have to somehow prove the derivative of a or v to be zero, but i have no idea...
  17. K

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    Homework Statement A research balloon of total mass 410 kg is descending vertically with a downward acceleration of 1.0 m/s2. How much ballast must be thrown from the car to give the balloon an upward acceleration equal to 1.6 m/s2, presuming that the upward lift of the balloon does not...
  18. S

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  19. A

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  20. P

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  21. science_rules

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  22. F

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  23. M

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  24. T

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  25. P

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  26. A

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  27. C

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  28. R

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  29. K

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  30. M

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  31. J

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  32. F

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  33. F

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  34. A

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  35. S

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  36. A

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  37. A

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  38. L

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  39. D

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  40. J

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  41. S

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  42. M

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  43. T

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  44. J

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  45. T

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  46. S

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  47. D

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  48. B

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  49. T

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  50. L

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