Physics> Constant Speed
An object whose speed of movement does not change has a constant speed in a single direction.
Learning challenge
 Learn the terms for constant speed and how to apply it to acceleration.
Key points
 Constant speed indicates that the object is moving in a straight line at a constant speed.
 The line can be rendered as x = x_{0} + vt, where x_{0} – the position of the object at t = 0, and the slope of the line indicates the speed.
 The speed can be positive or negative, which indicates in which direction the object is moving.
Term
Constant speed is movement that does not change speed or direction.
Constant speed is one of the simplest forms of movement. This type occurs when an object is moving at a constant speed with little friction, such as a hockey puck sliding on ice. To have a constant absolute speed, an object must have a constant scalar speed in a constant direction (only straight ahead).
Newton s second law (F = ma) says: if you act on an object by force, then it will receive acceleration. If the acceleration is equal to 0, then the object does not yield to any external forces. In mathematical terms, the equation looks like
a = dv / dt = 0 = v = const.
If the object is moving at a constant speed, then the graph of the distance between times displays the same position measurements at each time interval. Therefore, we find that x = x_{0} + vt. Here x_{0} – displacement at t = 0.
If an object moves at a constant speed, it does not change direction or speed, therefore it is displayed as a straight line
The speed of an object can also be obtained by recognizing its trail over time. Using the graph, the speed is calculated from the change in distance over the time change. Speed is shown schematically as the slope of the line. It can be positive and negative (the sign shows the direction of movement).
Physics Section  
Movement in two dimensions 
 
Vectors 
 
Projectile movement 
 
Multiple speeds 
