Speed is how fast something is going when the direction in which it is travelling is unimportant.
Velocity is a measurement of the rate at which an object is changing its position. As such, in order to measure it, one must define both the speed at which an object is moving, and also the direction of movement.
Speed and acceleration.
Velocity is the speed of an object.
Speed is scalar (that is, without direction) and velocity is a vector (speed plus direction) by definition in physics.
The official definition for the word group velocity is "the speed at which the energy of a wave travels."
This is not always the case. But if an object moves in a circle, at constant speed, its velocity will change. Velocity is a vector - consisting of the magnitude (the speed), and a direction. So by definition, if the direction changes, the velocity changes - you have a different vector.
Speed and acceleration.
By definition acceleration is the change in velocity (speed).
Velocity is the speed of an object.
Speed plus the direction of travel.
Speed is scalar (that is, without direction) and velocity is a vector (speed plus direction) by definition in physics.
No. It is a matter of definition. Acceleration is defined as a change of velocity. Technically, one must distinguish between velocity and speed. Velocity is a vector and includes the information about the magnitude (speed)and direction. One can have a constant speed and an acceleration (as in circular motion) but, by definition, constant velocity means zero acceleration.
The official definition for the word group velocity is "the speed at which the energy of a wave travels."
Meaning something that goes at extreme velocity.
That's the definition of its velocity vector.
If the speed of an object is cited and its direction of motion is also cited, we have the velocity of the object. Velocity is speed plus a direction vector.
This is not always the case. But if an object moves in a circle, at constant speed, its velocity will change. Velocity is a vector - consisting of the magnitude (the speed), and a direction. So by definition, if the direction changes, the velocity changes - you have a different vector.
Wind is simply the movement of air. By definition, this movement has velocity (it has speed plus a direction).