Physics Speed, Velocity & Acceleration Review

Speed, Velocity & Acceleration

• Speed: Rate of motion quantifying how quickly an object changes position.
• Velocity: Combines speed with direction, indicating the object's rate of motion towards a specific point.
• Acceleration: Measures how quickly velocity changes; includes both changes in speed and direction.

Mathematical Formulas

• Speed Formula: Calculated as distance divided by time (distance/time).
• Acceleration Formula: Change in velocity over time ((change in velocity)/time).

Units of Measurement

• Speed Unit: The International System (SI) unit for speed is meters per second (m/s).
• Acceleration Unit: The SI unit for acceleration is meters per second squared (m/s²).

Types of Acceleration

• Positive Acceleration: Indicates an increase in speed; the object is speeding up.
• Negative Acceleration: Signifies a decrease in speed; the object is slowing down.
• Zero Acceleration: Reflects constant speed; no change in speed or direction.

Instruments and Concepts

• Speedometer: Device used to measure the speed of a vehicle.
• Instantaneous Speed: Speed of an object at a specific moment in time.
• Motion: Describes an object's change in position relative to a reference point.
• Reference Point: A location or object utilized to compare and determine if another object is in motion.

Key Comparisons

• Distance vs. Displacement:
  • Distance: Total movement regardless of direction.
  • Displacement: Straight line measurement from starting position, including direction.

Questions to Consider

• Is a car turning left at a constant speed accelerating? Yes, because it is changing direction.
• Is a car moving forward at a constant speed accelerating? No, as there is no change in speed or direction.
• What is faster, the speed of sound or the speed of light? The speed of light is faster than the speed of sound.