1. Understanding Speed

Speed is the distance traveled by an object per unit of time. It tells us how fast an object is moving but not the direction.

Formula for Speed:

Speed=Distance/Time

• Distance is measured in meters (m) or kilometers (km).
• Time is measured in seconds (s) or hours (h).
• Speed is usually expressed in meters per second (m/s) or kilometers per hour (km/h).

2. Understanding Velocity

Velocity is speed with direction. It tells us how fast an object moves and in which direction.

• Displacement is the shortest straight-line distance between the starting and ending points, including direction.
• Velocity is a vector quantity, meaning it has both magnitude (speed) and direction.

📌 Example:

• A car moving north at 60 km/h has a velocity of 60 km/h north.
• If a bus is moving east at 40 km/h, its velocity is 40 km/h east.

✅ Key Point: If an object changes direction, its velocity also changes—even if the speed remains the same.

3. Acceleration: The Rate of Change of Velocity

Acceleration is how quickly an object changes its velocity over time. It occurs when an object:

• Speeds up (positive acceleration).
• Slows down (negative acceleration or deceleration).
• Changes direction (even at a constant speed).

4. Types of Motion Based on Velocity & Acceleration

1️⃣ Uniform Motion – The object moves at a constant speed without changing direction (zero acceleration).

• Example: A car moving at 60 km/h on a straight road.

2️⃣ Non-Uniform Motion – The object’s speed or direction changes (acceleration present).

• Example: A car stopping at a red light or a roller coaster going downhill.

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