Force of Gravity: The downward pull experienced by objects near Earth's surface due to gravity. It is responsible for the weight of objects and can affect their motion on inclined planes.
Friction: The force that opposes the motion or attempted motion between two surfaces in contact. On an inclined plane, friction can either aid or hinder the object's movement depending on its direction and magnitude.
Angle of Inclination: The angle between the inclined plane and a horizontal line. It determines how steep or shallow the incline is and affects both the gravitational force component along the slope and the amount of effort required to move objects up or down.