What's the difference between vector and velocity in physics?

Question

So I just asked the question what's the difference between vector and trajectory.

Here is the answer I got:
"A vector is simply speed and direction, at the instant of measurement or whenever it applies.

Trajectory is an entire path, as in the trajectory of a cannon shell or a thrown ball - a curve with changing speeds, as it's pulled down by gravity and slowed by air drag.

The vector continuously changes during the flight of the object."

What's the difference between vector and velocity then?

Mr. Smartypants · Accepted Answer

A vector is a straight line that begins here and ends there.  Think of a line segment in 2-dimensional or 3-dimensional space--a straight line between two points.  There's no speed there, it's just a number with both direction and magnitude.  Velocity is not involved!

In the real world it gets a little more complicated.  If you hit a golf ball, there's a vector there.  The direction depends on where you contacted the ball and what direction the club was swinging.  The magnitude is how hard you hit the ball.  The initial vector is a straight line of a specific length.  But once the ball is in flight it's influenced by gravity and wind resistance which continually modify both the direction and magnitude of the vector.  At any given point in the ball's flight, the vector is instantaneous.  The next millisecond it will be a different vector.

With a golf ball, velocity is proportional to magnitude.  But that's not always the case.  A GPS can give you a 2-dimensional vector from where you are to somewhere else.  It's this far (magnitude) at this compass  heading (direction).  Velocity is not involved at all!

? · Answer

A cannon fires a projectile,  Three vectors  determine the flight .  A velocity  vector  has the
projectile traveling along a straight line at a constant speed.   Unless you  are in outer space with no air , a second vector appears and this vector is in the opposite direct ion and 
constantly changes with the speed and 
 projectile streamlining.  Another vector is the gravity  vector - the force pulling the projectile 
towards the earth. Vectors always a force or velocity married to a direction.

Jim · Answer

Vector is a general purpose term, not specific to speed.

It is a 'Line segment' with a given direction and a magnitude:
"A Euclidean vector is frequently represented by a line segment with a definite direction, or graphically as an arrow, connecting an initial point A with a terminal point B,[3] and denoted by A B → . {&#92;overrightarrow {AB}}."

All velocities are vectors. Velocity is 'speed with a direction'.

But I could also have a force vector, a magnetic vector, a gravity vector, etc.

Anonymous · Answer

Vector is velocity along with direction....

What's the difference between vector and velocity in physics?

4 Answers