Can an object have a constant velocity and still have varying speed? explain.?

Question

explain..

Answer 1

No.
Velocity is a vector, which means it has a magnitude and direction.
Speed is a scalar, which means it has only a magnitude and no direction.
So if the speed changes, the scalar value changes and so does the velocity (because the magnitude changes).

However the reverse is possible. An object can have constant speed but varying velocity. This is because although the magnitude/scalar values remain constant, the direction of the velocity may change. An example is the moving of a car around a bend at a constant speed, but the velocity changes because of the change in direction. (Velocity is a vector).

Answer 2

Velocity is "rate of change of position.
Velocity is a "vector", which means
that it has a value AND a direction.
Speed has only a value; no direction.

You can go North at a speed of 20 miles per hour,
or South or West at the same speed,
or in any other direction at exactly the same speed.
Your velocity would be different in each case,
but the speed would be the same.

If the velocity is constant,
then BOTH the speed and the direction are constant.

It is possible to keep the speed constant
but change the velocity. For example,
a satellite (or planet) in a perfectly-circular
orbit would have a constant speed but a
constantly-changing direction.

However, if the velocity is constant,
that means that the direction is constant
and the speed is also constant.
I see no way to vary the speed without changing the velocity.

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One further thought: speed is often regarded as the absolute magnitude of velocity, so going North at a rate of 20 mph
can also be thought of as going going South at a rate of
NEGATIVE 20 mph; in both cases, the speed is the same.

I suppose one could say that a particle (or person)
moving back and forth along a line could have a constant
speed and direction, if it (or he) first went forward at
a constant speed then instantly changed velocity by going backwards at the the same speed. In such a case, the ABSOLUTE speed and the direction are both constant, so I can imagine someone getting confused by the definition and thinking that the velocity must also be constant -- even tho it is NOT.

Sometimes we write "s = | v |"
where s is speed (a scalar) and v is velocity (a vector).
You can take apart the vector, into a value and a direction,
and you can ignore the sign for the value and still call it speed.
However, if you ignore the negative value and call it a positive speed, you can't put it back together and get the same velocity vector.

Answer 3

No. Velocity has magnitude and direction. The magnitude of this velocity is basically its speed, but it must have a direction in order to be a velocity. So if we say that the velocity is constant and then change the speed ( which is the magnitude of the velocity) then it would not be constant.

Answer 4

A man can walk at constant velocity inside a moving train , and if the train changes its speed , this amounts to an object (man)of constant velocity moving with variable speeds. You can have an object instead of a man.

Answer 5

yes, wind drag.