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Basic kinematics

  1. Nov 10, 2005 #1
    Can there be any other case than rotating when the velocity of a body never becomes zero and still constantly changes in such a way that rate of change of magnitude of velocity is always zero(dv/dt = 0), i.e. the magnitude of velocity is constant?
  2. jcsd
  3. Nov 10, 2005 #2

    Chi Meson

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    For velocity to change its direction without changing its magnitude it must experience a net force that is perpendicular to its direction of motion. If this force remains constant in direction, then parabolic motion (such as projectile motion) is the result.

    If the force also changes its direction so as to constantly stay perpendicular to motion, then circular motion is the result. One could get clever and make a space ship that has many thrusters mounted around the ships middle, all pointing perpendicular to the ships heading. If a computer managed to fire these such that only one was on at any moment, the ship could take a wiggling path, following many arcs through space, but always at a constant speed.
  4. Nov 10, 2005 #3
    well it is easy, take a bike try to do all the maneuver u can while keeping the speed constant but changing direction.
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