• Unbalanced forces acting on an object cause the object to accelerate. • The combination of foces acting on an object is net force; acceleration depends in net force. • Doubling the force on an object doubles its acceleration. • An object’s acceleration is directly proportional to the net force acting on it. 6.2 Mass Resists Acceleration
• For a constant force, an increase in the mass will result in a decrease it the acceleration. • The same force applied to twice as much mass result is only half the acceleration. • For a given force, the acceleration produced is inversely proportional to the mass. Inversely means that the two values change in opposite directions. 6.3 Newton’s Second Law
• Newton’s second law states that the acceleration produced by a net force on an object is directly proportional to the magnitude of the net force, is in the same direction as the net force, and is inversely proportional to the mass of the object. • Newton’s second law describes the relationship among an object’s mass, an object’s acceleration, and the net force on an object. • In equation form, Newton’s second law is written as follows:
• Acceleration is equal to the net force divided by the mass. 6.4 Friction
• The force of friction between the surfaces depends on the kinds of material in contact and how the surfaces are pressed together. • Friction acts on materials that are in contact with each other, and it always acts in a direction to oppose relative motion. • Liquids and gases are called fluids because they flow. Fluid friction occurs when an object moves through a fluid. • Air resistance is the friction acting on something moving through air.
Chapter 6 Newton’s Second Law of...