1. Using Displacement and Time:
* Formula: Velocity (v) = Displacement (Δx) / Time (Δt)
* Explanation: Velocity is the rate of change of an object's position.
* Example: A car travels 100 meters east in 5 seconds. Its velocity is 100 meters / 5 seconds = 20 meters per second east.
2. Using Initial Velocity, Acceleration, and Time:
* Formula: Final velocity (v) = Initial velocity (u) + Acceleration (a) * Time (t)
* Explanation: This formula is useful when an object is accelerating uniformly.
* Example: A car starts at rest (u = 0 m/s) and accelerates at 2 m/s² for 10 seconds. Its final velocity is 0 + (2 m/s²) * (10 s) = 20 m/s.
3. Using Initial Velocity, Acceleration, and Displacement:
* Formula: v² = u² + 2aΔx
* Explanation: This formula is helpful when you know the displacement and want to find the final velocity.
* Example: A ball is thrown upwards with an initial velocity of 10 m/s. It reaches a maximum height of 5 meters. What is its velocity at that height?
* u = 10 m/s, a = -9.8 m/s² (due to gravity), Δx = 5 m.
* v² = 10² + 2 * (-9.8) * 5
* v² = 0
* v = 0 m/s (The ball momentarily stops at its highest point).
Key Points to Remember:
* Velocity is a vector: It has both magnitude (speed) and direction.
* Units of Velocity: The most common unit of velocity is meters per second (m/s).
* Constant Velocity: If an object is moving at a constant speed in a straight line, its velocity is constant.
* Changing Velocity: If an object's speed or direction changes, its velocity changes. This means the object is accelerating.
Let me know if you have a specific problem you'd like help with, and I can provide a step-by-step solution!
