The speed and velocity of an object are equal when the object is moving in a straight line with a constant speed.
Speed is a scalar quantity that only considers the magnitude of the motion and is defined as the rate of change of distance traveled with respect to time. So, if an object is moving at a constant speed, its speed remains the same over time.
Velocity, on the other hand, is a vector quantity that takes into account both the magnitude and direction of motion. It is defined as the rate of change of displacement (change in position) with respect to time. When an object is moving in a straight line with constant speed, its displacement and distance traveled are the same, and thus the velocity is equal to the speed, as the direction remains constant.
However, it's essential to note that when an object is moving in a curved path, its speed and velocity are not equal, as the direction of motion is constantly changing. Velocity also accounts for changes in direction, while speed does not.