Speed is the size of velocity. But velocity also has a direction. "30 miles per hour" is speed. "30 miles per hour north" is velocity.
Velocity is speed and its direction. "30 miles per hour" is a speed. "30 miles per hour north" is a velocity". "30 miles per hour north" and "30 miles per hour south" are identical speeds but different velocities.
Velocity tells the speed AND what direction it's in. -- "30 miles per hour" is a speed. -- "30 miles per hour north" is a velocity. -- "30 miles per hour east" and "30 miles per hour south" are the same speed but different velocities.
Velocity is speed plus direction. If you say you are traveling at 54 miles per hour, you are giving your speed. If you say you are going north at 54 miles per hour, you are giving your velocity.
'Velocity' should be compared with 'speed', and it should be understood that they're different. "30 miles per hour" is a speed. "30 miles per hour toward the south" is a velocity.
If no direction is mentioned, then you have a speed. Example: "30 miles per hour". If the direction is mentioned, then you have a velocity. Example: "30 miles per hour north".
a) A speed, b) a velocity.
Speed or velocity.
Speed or velocity.
Velocity tells the speed and also the direction. "30 miles per hour north" and "30 miles per hour west" are the same speed but different velocities.
Velocity is a vector, which means it has a direction, but speed isn't. Speed is the absolute value of velocity. Velocity can be negative, meaning that the speed is opposite to the direction that you're calling the positive direction.
No. It is a speed (a scalar) but not a velocity (a vector).