* Speed: The object is speeding up or slowing down.
* Direction: The object is changing direction, even if its speed remains constant (like a car going around a curve).
In simpler terms, acceleration is the rate at which the velocity of an object changes.
Here's a breakdown:
* Constant velocity: An object moving at a constant speed in a straight line has zero acceleration.
* Increasing speed: An object speeding up has positive acceleration.
* Decreasing speed: An object slowing down has negative acceleration (sometimes called deceleration).
* Changing direction: An object changing direction, even if its speed remains constant, has acceleration.
Examples:
* A car speeding up from a stoplight is accelerating.
* A car slowing down to a stop is accelerating (negatively).
* A car turning a corner at a constant speed is accelerating because its direction is changing.
* A ball thrown straight up in the air is accelerating due to gravity.
Important note: Acceleration is a vector quantity, meaning it has both magnitude (how much it's changing) and direction.
