interaction between mass & force

• weight is how much gravity pulls on an object
• force is what makes objects move or change direction
• mass is the amount of matter an object has
• FORCE - The resultant effect of a push or pull on an object.
• MAGNITUDE - refers to the side or strength of the force. It is commonly expressed in Newton(N)
• Line of action - is the straight line passing through the point of application and is parallel to the direction of the force
• point of application - the point at which the force is applied to the object, the point of contact
• Balanced forces - forces that are equal in magnitude and opposite in direction.
• friction - acts opposite the direction of motion and slows down the object
• If the sum of the forces equate to zero, they are considered BALANCED
• If the algebraic sum is not zero, then the forces is not balanced/UNBALANCED
• Newton's first law of motion: LAW OF INERTIA
• LAW OF INERTIA - An object will remain at rest or continue moving at a constant velocity unless acted upon by a resultant force
• Newton's second law of motion - LAW OF ACCELERATION
• F = ma (force equals mass times acceleration)
• The greater the mass, the more difficult it is to change its state of motion.
• Law of acceleration - is directly proportional to the magnitude of the net force acting on it and inversely proportional to the mass of the object
• Net Force - The total amount of forces that are acting on an object
• Acceleration = net force /mass
• Force has a unit and expressed as Newton's(N)
• 1 Newton's(N) = 1kg/ms2
• when object fall, their velocities increase by 9.8 m/s2 every 1 second
• Newton's third law of motion: LAW OF INTERACTION(action-reaction)
• Law of interaction(action-reaction) - "for every action, there is an equal and opposite reaction"
• Forces can be contact or non-contact
• non-contact forces, on the other hand, are forces that occur when the fields around objects (e.g. gravitational field, electric field, or magnetic field) interact with another field located around another body
• 1 lb = 4.45 N 1N = 0.225 lb
• The third law of motion also known as the Law of Interaction is stated as: “Whenever one object exerts a force on a second object, the second object exerts an equal force on the first
• Work is application of force, f𝑓, to move an object over a distance, d, in the direction that the force is applied. W=fd
• force is not required to move an object at constant velocity.
• Energy - can be defined as the ability to do work.
• mechanical energy, which comes in two forms: kinetic energy and potential energy.
• Kinetic energy depends on the mass of an object and its velocity, v.

  KE=12mv2
• The joule (J) is the metric unit of measurement for both work and energy.
• Work - energy transferred by a force
• work = force x distance
• Power is the rate at which work is done.
• Power = work/time (P=W/t
• Power can be expressed in units of watts (W).
• The watt unit was named after James Watt( a Scottish engineer )