Physics Unit: Force & Motion What is physical science? A. Physical science is a field of science that studies matter and energy. B. Physical science has 2 main branches: 1. PHYSICS: the study of how matter and energy interact robotics, nuclear energy, solar panels 2. CHEMISTRY: the study of the structure, makeup, and changes of matter chemicals, acids & bases, medicines
What is energy? A. ENERGY: the ability to do work or make something happen B. All forms of energy fall under two categories: 1. POTENTIAL ENERGY: stored energy that could make something happen a. Chemical Energy b. Nuclear Energy c. Stored Mechanical Energy d. Gravitational Energy 2. KINETIC ENERGY: used energy that is making something happen a. Radiant Energy b. Thermal Energy c. Motion d. Electrical Energy e. Sound
What are the different forms of energy? A. There are many different forms of energy to make things happen. B. Below are 6 of the major forms: 1. MECHANICAL ENERGY: the energy in moving objects 2. ELECTRICAL ENERGY: energy from the flow of electrons 3. ELECTROMAGNETIC ENERGY: energy in the form electrical and magnetic waves that can travel through space 4. HEAT ENERGY: thermal energy that comes from moving particles of matter (friction) 5. CHEMICAL ENERGY: energy that holds particles of matter together (chemical bonds) 6. NUCLEAR ENERGY: energy stored in an atom s nucleus
What is a wave? A. WAVE: a disturbance that transports energy from one place to another. 1. A wave is energy that travels over a distance. 2. There are two major forms of waves: a. MECHANICAL WAVES: waves that travel through matter like air or water b. ELECTROMAGNETIC WAVES: waves that can travel through matter or empty space
What is a wave? B. Waves that travel through matter can do it one of two ways: 1. TRANSVERSE WAVE: waves that move up and down a. There are two parts to a transverse wave i. CREST: the highest point of a wave ii. TROUGH: the lowest point of a wave 2. LONGITUDINAL WAVE: waves that move back and forth a. There are two parts to a longitudinal wave i. COMPRESSION: where the particles are close together ii. RAREFACTION: where particles are far apart
What is mechanical energy? A. MECHANICAL ENERGY: the energy an object has that causes it to move B. Mechanical energy can come in one of two ways: 1. STORED MECHANICAL ENERGY: potential mechanical energy that could cause an object to move 2. MOTION: kinetic mechanical energy that causes an object to move C. A force acting on an object is required for mechanical energy
What is a Force? A. FORCE: a push or pull exerted on an object B. To describe a force, you must know a force s size and direction C. Size and direction can cause one of two situations: 1. BALANCED FORCES: forces on an object equal in size but opposite in direction 2. UNBALANCED FORCES: forces on an object that are no longer balanced, causing a change in the motion of an object
What is a Force? D. Forces are drawn as arrows of different sizes. 1. Arrows show direction 2. Different sizes show how strong the force is E. Forces are measured using instruments: 1. A spring scale is used to measure a force using Newtons 2. NEWTON: a standard unit of force depicted as an N 3 N 3 N 1 N 3 N 10 N 8 N
Which major forces affect the motion of objects? A. Gravity is one of the major forces acting on objects 1. GRAVITY: a force of attraction between all objects in the universe B. On Earth, objects are pulled to the center of the planet by the dense mass of the planet s core C. Friction is another major force moving objects must contend with: 1. FRICTION: a force that pushes back on a moving object 2. This force often occurs when an object moves over or through another type of matter
What is Magnetism? A. MAGNETISM: the force (push or pull) produced by magnetic materials B. MAGNET: a material that pulls or attracts the metals iron, cobalt, and nickel 1. All magnets have two common properties: a. MAGNETIC POLES: two places on a magnet where the forces are the strongest i. The two poles are marked North (N) and South (S) ii. Opposite poles are attracted to each other iii. Similar Poles repel each other b. MAGNETIC FIELD: the space around a magnet where the force acts on other objects
What is Magnetism? C. Permanent magnets can cause iron, cobalt, or nickel to become temporary magnets. 1. Each atom in an object as positive and negative end 2. When metals are pulled on by a magnetic field, these ends line up, with positive being attracted to negative. 3. This lining up creates a magnetic field around the metal