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Newton’s Laws and Types of forces. An object at rest remains at rest, an object in motion remains in motion (in the same direction with constant speed) unless acted upon by an outside force. . Newton’s First law. Newton’s First Law is also known as the Law of INERTIA . Cement Ball Prank
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An object at rest remains at rest, an object in motion remains in motion (in the same direction with constant speed) unless acted upon by an outside force. Newton’s First law
Newton’s First Law is also known as the Law of INERTIA. Cement Ball Prank Definition of Inertia: The resistance an object has to a change in its state of motion. (1) This is why an object at rest wants to remain at rest and an object in motion wants to remain in motion. (2) This is also why more massive objects have more inertia. Or law of inertia
States the relationship between force, mass and acceleration of an object. F = ma is the mathematical representation of the Newton’s 2nd law. Newton’s second law
States that for every action force, there is an equal and opposite reaction force. NOT THIS TYPE OF REACTION The action-reaction pair act on different objects. Newton’s third law
Force is a push or pull on an object. Force is a vector, hence the direction in which it is applied matters. We will be studying four major types of forces: Gravitational, Tension, Frictional, and Normal and of course there might applied force too. SI unit of force is Newton (kg-m/s2) Types of forces
This is the force with which gravity pulls on an object. Since gravity always pulls down, Fg always acts in the downward direction. Gravitational force Fg
Fg is the force exerted by a mass due to gravity. Newton’s 2nd Law F=ma So, Fg=mg Mass, “m” is the matter that occupies space. Mass does not depend on gravity. Its unit is kilograms. Weight(Fg) depends on gravity. Weight of an object is more on earth than on moon as Earth’s gravity is more than moon’s gravity. Its Unit is Newton. Gravitational force
This is the force due to a string or a rope. Tension force, FT always acts along the string. Multiple strings or ropes imply multiple tensions. Tension force FT
This is the force due to rubbing of two surfaces. There are two types of frictional forces: 1) Static Friction, Ffs 2) Kinetic Friction, Ffk Frictional force always acts opposite to the direction of motion. Frictional force
Static Friction, Ffs = µsmg And Kinetic Friction, Ffk = µkmg µs and µk are coefficients of static and kinetic friction. Coefficients of friction depend only on the types of material that produce friction. Frictional force on horizontal surfaces
This is the force due to the support of a surfaces. Normal force, FN always acts perpendicular to the surface that is supporting the object. FN normal force
Fair Drag Fair Drag FN Ff Fapp Fg Fg Fg Applying all or any of these forces on an object is called a free body diagramming. The first free body diagram will produce a net force. The 2nd & 3rd free body diagrams are balanced, so net force is zero. Free Body diagram
These vector when added might produce net force. If the net force of a system is zero, then it is said to be a stable or balanced system. It is also said to be in equilibrium. If the net force of a system is NOT zero, then it is said to be an unstable or unbalanced system. Net force
Unbalanced systems produce net force, hence the system undergoes some acceleration. The acceleration of the system depends on the mass of the system. Unbalanced systems