Question

what is the difference between speed and velocity

Answer 1

speed is a scalar quantity because it has only magnitude.(example:-9 km/hr)
velocity is a vector quantity because it has magnitude as well as direction.(example:-9km/hr towards north)

Answer 2

Speed is a scalar quantity -: It is the magnitude of the velocity .Speed is measured in units of distance divided by time.For example miles per hour,feet per hour,etc.
Velocity is a vector quantity-: When giving the velocity we must specify the magnitude and the direction of travel.For example you might drive 100km/h in a northerly direction