velocity

Examples of velocity in the following topics:

• Relative Velocity

  • Relative velocity is the velocity of an object B measured with respect to the velocity of another object A, denoted as $v_{BA}$.
  • Relative velocity is the velocity of an object B, in the rest frame of another object A.
  • Is the velocity of the fly, $u$, the actual velocity of the fly?
  • No, because what you measured was the velocity of the fly relative to the velocity of the boat.
  • The velocity that you observe the man walking in will be the same velocity that he would be walking in if you both were on land.

• Instananeous Velocity: A Graphical Interpretation

  • Instantaneous velocity is the velocity of an object at a single point in time and space as calculated by the slope of the tangent line.
  • Typically, motion is not with constant velocity nor speed.
  • However, changing velocity it is not as straightforward.
  • Since our velocity is constantly changing, we can estimate velocity in different ways.
  • Motion is often observed with changing velocity.

• Relativistic Addition of Velocities

  • A velocity-addition formula is an equation that relates the velocities of moving objects in different reference frames.
  • A velocity-addition formula is an equation that relates the velocities of moving objects in different reference frames.
  • As Galileo Galilei observed in 17th century, if a ship is moving relative to the shore at velocity $v$, and a fly is moving with velocity $u$ as measured on the ship, calculating the velocity of the fly as measured on the shore is what is meant by the addition of the velocities $v$ and $u$.
  • Since this is counter to what Galileo used to add velocities, there needs to be a new velocity addition law.
  • This change isn't noticeable at low velocities but as the velocity increases towards the speed of light it becomes important.

• Addition of Velocities

  • Relative velocities can be found by adding the velocity of the observed object to the velocity of the frame of reference it was measured in.
  • As learned in a previous atom, relative velocity is the velocity of an object as observed from a certain frame of reference.
  • demonstrates the concept of relative velocity.
  • When she throws the snowball forward at a speed of 1.5 m/s, relative to the sled, the velocity of the snowball to the observer is the sum of the velocity of the sled and the velocity of the snowball relative to the sled:
  • The magnitude of the observed velocity from the shore is the square root sum of the squared velocity of the boat and the squared velocity of the river.

• Flow Rate and Velocity

  • A fluid in motion has a velocity, just as a solid object in motion has a velocity.
  • Like the velocity of a solid, the velocity of a fluid is the rate of change of position per unit of time.
  • The flow velocity vector is a function of position, and if the velocity of the fluid is not constant then it is also a function of time.
  • In SI units, fluid flow velocity is expressed in terms of meters per seconds.
  • The magnitude of the fluid flow velocity is the fluid flow speed.

• Constant Velocity

  • An object moving with constant velocity must have a constant speed in a constant direction.
  • Motion with constant velocity is one of the simplest forms of motion.
  • You can also obtain an object's velocity if you know its trace over time.
  • In graphical terms, the velocity can be interpreted as the slope of the line.
  • Examine the terms for constant velocity and how they apply to acceleration

• Average Velocity: A Graphical Interpretation

  • Average velocity is defined as the change in position (or displacement) over the time of travel.
  • In everyday usage, the terms "speed" and "velocity" are used interchangeably.
  • This distinction becomes more apparent when we calculate average speed and velocity.
  • His average velocity would be:
  • Therefore, your average velocity, or displacement over time, would be 0 m/s.

• Constant Velocity Produces a Straight-Line

  • If a charged particle's velocity is parallel to the magnetic field, there is no net force and the particle moves in a straight line.
  • If an object experiences no net force, then its velocity is constant: the object is either at rest (if its velocity is zero), or it moves in a straight line with constant speed (if its velocity is nonzero).
  • If the acceleration is zero, any velocity the particle has will be maintained indefinitely (or until such time as the net force is no longer zero).
  • If the magnetic field and the velocity are parallel (or antiparallel), then sinθ equals zero and there is no force.
  • In the case above the magnetic force is zero because the velocity is parallel to the magnetic field lines.

• Rotational Angle and Angular Velocity

  • Although the angle itself is not a vector quantity, the angular velocity is a vector.
  • Angular acceleration gives the rate of change of angular velocity.
  • A fly on the edge of a rotating object records a constant velocity $v$.
  • The object is rotating with an angular velocity equal to $\frac{v}{r}$.
  • The direction of the angular velocity will be along the axis of rotation.

• Angular Velocity, Omega

  • The units for angular velocity are radians per second (rad/s).
  • Angular velocity ω is analogous to linear velocity v.
  • A car moving at a velocity v to the right has a tire rotating with an angular velocity ω.
  • A larger angular velocity for the tire means a greater velocity for the car.
  • Examine how fast an object is rotating based on angular velocity