What is the rate of change of velocity?

The rate of change of velocity is called acceleration. In physics terms:

Acceleration = Change in velocity / Time taken

Or in calculus terms: a = dv/dt (derivative of velocity with respect to time)

Key points about acceleration: - It's a vector quantity - has both magnitude and direction - Positive acceleration means velocity is increasing - Negative acceleration (deceleration) means velocity is decreasing - Zero acceleration means constant velocity (could be zero or any constant speed) - Units are typically meters per second squared (m/s²)

Everyday examples: - A car speeding up (positive acceleration) - A ball thrown upward slowing down (negative acceleration due to gravity) - A car turning at constant speed (accelerating because direction changes)

Understanding acceleration is crucial in physics because it relates directly to force through Newton's Second Law (F = ma). It's not just about "speeding up" - any change in velocity (speed OR direction) involves acceleration!