# Offers a greater resistance to change from its state

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offers a greater resistance to change from its state of motion. • Object with larger mass has larger inertia to resist the attempt to change the state of motion.
MA/UiTM/PHY130/2015 APPLICATIONS OF NEWTON’S LAWS
MA/UiTM/PHY130/2015 5.1.2 Newton’s 2 nd Law Of Motion States that the “The acceleration of an object is directly proportional to the net force acting on it and is inversely proportional to its mass. The direction of the acceleration is in the direction of the net force acting on the object”. NEWTON’S LAW OF MOTION
MA/UiTM/PHY130/2015 NEWTON’S LAW OF MOTION
MA/UiTM/PHY130/2015 NEWTON’S LAW OF MOTION
MA/UiTM/PHY130/2015 5.1.2 Newton’s 3 rd Law Of Motion States that the “For every action there is an equal and opposite reaction. The force acted on each body are equal in magnitude and in opposite direction.” NEWTON’S LAW OF MOTION
MA/UiTM/PHY130/2015 NEWTON’S LAW OF MOTION
MA/UiTM/PHY130/2015 NEWTON’S LAW OF MOTION
MA/UiTM/PHY130/2015 GRAVITY AND NORMAL FORCE Normal force, F N is the force exerted on an object that is perpendicular to the surface of contact. Gravitational force, W is the force exerted on an object due to the attraction of gravity, also called as weight
MA/UiTM/PHY130/2015 GRAVITY AND NORMAL FORCE Gravitational Force (Weight, ) ? Is defined as the force exerted on a body under gravitational field. A vector quantity Dependent on location (because g varies with location) Always directed towards the earth’s center or same direction of acceleration due to gravity, g. S.I. unit: kg m? −2 or newton (N).
MA/UiTM/PHY130/2015 Applications of Newton’s law problem can be easily solved using free body diagram. Free body diagram is a diagram to show all forces acting on an object in a given situation without the body. 4 Steps taken to draw a free body diagram: 1. Identify all the forces acting on the object. 2. Draw all the forces acting on the object. 3. If it involves more than one object, draw a separate free body diagram for each object. 4. Apply the equation below: APPLICATIONS OF NEWTON’S LAWS For along x-axis For along y-axis a m F F net y y a m F x x a m F
MA/UiTM/PHY130/2015 Case 1: If an object at equilibrium on horizontal surfaces APPLICATIONS OF NEWTON’S LAWS F N mg Object static (not moving), a = 0 ms -2 Forces on the object: 1. Normal force, F N 2. Weight of object, W = mg F x = 0 F y = 0 F N – mg = 0 F N = mg
MA/UiTM/PHY130/2015 Case 2: If an object accelerates on horizontal surfaces (frictionless) APPLICATIONS OF NEWTON’S LAWS Object hanging (not moving). Forces on the object: 1. Tension force, T 2. Weight of object, W = mg F N mg F (pull) a floor F x = ma F = ma F y = 0 T – mg = 0 T = mg
MA/UiTM/PHY130/2015 Example 1 Find the acceleration , a & normal force, F N of object B. (Ans.: a = 0.67 m/s 2 ; F N = 29.43 N) APPLICATIONS OF NEWTON’S LAWS F = 2 N a B = 3 kg
MA/UiTM/PHY130/2015 Example 2 Find the acceleration , a of object C.