* Newton's Second Law: This law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.
* F = ma (Force = mass x acceleration)
* Forces and Acceleration:
* Increase in Acceleration: A force in the direction of motion will increase acceleration.
* Decrease in Acceleration: A force *opposite* to the direction of motion will decrease acceleration (or cause deceleration).
* Zero Acceleration: A net force of zero results in zero acceleration (constant velocity or rest).
Examples:
* Friction: Friction acts opposite to the direction of motion, causing a decrease in acceleration (slowing things down).
* Air Resistance: This force acts opposite to the direction of motion of an object through the air, causing a decrease in acceleration.
* Brakes: When you apply brakes on a car, they exert a force opposite to the direction of motion, slowing the car down.
Important Note: It's crucial to understand that forces are *agents* of change in motion. They can cause acceleration to increase, decrease, or remain constant.
