Question

In your own words, explain the difference between the velocity of an object and its speed.

Short answer

The key difference between speed and velocity lies in that speed, which is a scalar quantity, is only concerned with how fast an object is moving while velocity, a vector quantity, involves both the speed and the direction of the object.

Step-by-step solution

Definition of Speed

Firstly, let's explore the definition of speed. Speed is a measure of how quickly an object moves. It's a scalar quantity, which means it only involves magnitude (the numerical value), not direction. The standard international unit for speed is meters per second (m/s). For example, if a car covers 60 meters in 2 seconds, its speed would be 30 m/s.

Definition of Velocity

Now, let's examine the definition of velocity. Velocity is the rate of change of displacement of an object. It's a vector quantity, which implies it involves both magnitude and direction. For example, if an object moves towards the north at 10 m/s, the velocity is 10 m/s, North.

Distinguishing Speed and Velocity

With the definitions of speed and velocity, we can now identify their differences. The key difference lies in that speed is a scalar quantity (only involves the magnitude) whereas velocity is a vector quantity (involves both magnitude and direction). In other words, velocity includes an element of direction which speed does not.