650 likes | 661 Views
Forces. Force and Net Force. Force is a push or a pull on an object. Net force is the total force on an object. Unbalanced Force Balanced Force. The balanced forces are the forces in equal and opposite directions.
E N D
Force and Net Force • Force is a push or a pull on an object. • Net force is the total force on an object.
Unbalanced ForceBalanced Force • The balanced forces are the forces in equal and opposite directions. • Unbalanced Forcecan cause an object to move, stop moving, or change direction.
Newton’s First Law Inertia Greater mass means Greater inertia • An object at rest will stay at rest unless acted upon by an outside force. • Inertia is every objects resistance to change its motion.
Newton’s Second Law • The acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the object’s mass.
Force=mass x acceleration F=m x a • Or • a = Force/ mass • a = F/m
Equation for Newton It’s the same as the force equation! • Newton=m x a.
Sometimes we might calculate mass using Force and Acceleration • Mass=Force/Acceleration • m=F/a
How much Force was required to make a 2000kg car accelerate at 5m/s? • 400N • 0.001N • 10,000N
If you drop a 15kg bowling ball with a Force of 147N, what is it’s acceleration? • 9.8m/s/s • 0.1m/s/s • 2,205m/s/s
A person throws a baseball at an acceleration of 25m/s/s with 12.5N of Force. What’s the Mass of the ball? • 312kg • .5kg • 2kg
4 Types of Friction • The 4 types of friction are: • Sliding friction (strongest) • Rolling friction • Fluid friction (weakest). • Static friction
2 Factors of Friction • 1-Type of surface. • 2-How hard the two surfaces push together.
Air Resistance and Weight • Air resistance is a type of fluid friction on falling objects. Weight is the force of gravity on an object at the surface of the Earth.
Law of Universal Gravitation • Gravity acts between all objects in the universe.
Gravity Between Objects • The force of gravity between objects increases with greater mass and decreases with greater distance.
Gravity is the force that pulls objects toward the Earth- acceleration due to gravity is 9.8m/s/s.
Newton’s Third law • If an object exerts a force on another object, the second object, exerts an equal force in the opposite direction.