Forces and Motion: Speed and Velocity

Speed represents how quickly an object is moving or the distance covered per unit of time; it can be calculated using the formula: Speed = Distance ÷ Time.
Constant speed means the object is moving at the same rate all the time, whereas varying speed means speed is changing over time due to acceleration or deceleration.
Velocity, like speed, measures the rate at which an object changes its position. However, velocity also considers the direction of movement, making it a vector quantity.
Velocity can be calculated using the formula: Velocity = Displacement ÷ Time. Here, displacement refers to the distance covered in a specific direction.
If the velocity of an object changes, it means the object is accelerating. Acceleration can occur due to an increase or decrease in speed or a change in direction.
The acceleration of an object can be calculated using the formula: Acceleration = (Final velocity - Initial velocity) ÷ Time.
When an object moves in a circle, even if its speed remains constant, its velocity changes due to a change in direction.
An object can be moving with a constant speed and yet be accelerating, such as in circular motion where the direction is constantly altering.
Graphs can represent movement: Distance-time graphs depict speed whereas velocity-time graphs depict acceleration.
The slope of a distance-time graph represents speed. A steep slope indicates higher speed.
The area under the curve in a velocity-time graph represents the distance travelled. A larger area indicates greater distance.
Deceleration (or negative acceleration) occurs when an object slows down and is represented by a downward slope in a velocity-time graph.
Uniform acceleration, including free falling objects, can be analysed using ‘suvat’ equations, which incorporate initial velocity (u), final velocity (v), acceleration (a), displacement (s), and time (t).