That is the case when you are talking about instantaneous speed and velocity - or when the velocity is constant. In the case of an average speed and velocity, this relation does not hold.
Always
speed has magnitude. velocity has magnitude and direction.
Acceleration.
Yes. Velocity is a quantity that has both magnitude and direction. Speed is the magnitude of velocity. If speed is constant but the direction is changing, then the velocity is changing. An example is a car turning a corner without slowing down.
Velocity refers to both speed and direction. A vector refers to both magnitude (the speed in this case) and a direction. Speed without reference to a direction is a scalar, a magnitude without direction.
http://wiki.answers.com/Q/The_difference_of_speed_and_velocity" The difference between speed and velocity is that speed is a scalar quantity(that have only magnitude) and velocity is a vector quantity(that have both magnitude and direction).
-- The magnitude of acceleration is equal to the time rate of change of speed. -- The magnitude of acceleration is equal to the time rate of change of the magnitude of velocity. -- Acceleration and velocity are both vectors.
Speed is equal to the magnitude of velocity almost always. Speed is total distance / total time no matter which way the distance goes. Velocity is the distance from a starting point divided by total time.
speed (magnitude of velocity)
Because speed is the magnitude of the velocity vector. The velocity consists of the speed and the direction, and the whole thing can be embodied in a 3D vector. If you like the velocity is the magnitude (the speed), which is a scalar (just a real number), multiplied by a unit vector in the right direction.
Velocity has magnitude and direction and speed only has magnitude.
velocity is a vector and speed is scalar. Velocity has magnitude and directions, with magnitude being speed. The magnitude of average velocity and average speed is the same.
Speed and velocity always have the same magnitude, becausespeed is the magnitude of velocity.The difference is that velocity has a direction but speed doesn't
speed has magnitude. velocity has magnitude and direction.
The speed is the MAGNITUDE of the velocity, i.e., without regard to the direction.
Then you can say that the object's speed and the magnitude of its velocity are constant, and the magnitude of its acceleration is zero.
Velocity is a vector, and so it has two components -- magnitude (speed) and direction. Speed is a scalar, and it is the magnitude of velocity, a vector.
It's not. Unless you add a direction to speed it will not become velocity. Since positive and negative are sometimes used to denote direction, absolute value of velocity may equal speed (certain situations)