## Competency 30 Physical Science

 force
 a push or pull on an object causing it to move, speed up, slow down, stop, or change direction can be constant speed or accelerate weight is also known as this
 universal forces
 gravitational, electrical, and magnetic are 3 types of…
 gravitational
 this force pulls any 2 objects toward one another example would be: stopping a swing from swinging
 weight
 an object has this because the force of gravity pulls down on the object a spring scale is used to measure this…
 Newtons 1st Law
 object at rest will remain at rest unless acted upon by force object in motion will remain at the same speed and direction unless acted by an outside force also known as inertia
 gravity
 a force that causes something to to move it pulls objects down or pulls 2 objects towards one another
 electrical
 this force pull or push forces that exists around charged particles like charges will repel – positive/positive unlike charges will attract – positive/negative
 magnetic
 this force attracts iron and steel
 repel
 north and north poles close together will
 attract
 north and south poles close together will…
 work
 the result of a force moving an object more gravity, more force will result in more of this to move an object less gravity, less force will result in less of this to move an object it is what is needed to move an object
 simple machines
 their primary job is to make work easier examples include: inclined plane, wedge, pulley, wheel and axle, lever, screw
 constant
 motion that does not change and is graphed with a straight line
 friction
 slows the motion of moving objects produces heat energy like rubbing your hand together
 kinetic energy
 energy of motion or moving examples: pushing a toy car down a ramp a child going down a slide
 potential energy
 stored energy such as a vehicle parked in the garage other examples include: a toy car on the top of a ramp a book placed near the end of a table
 kinetic energy
 loss of height increases this type of energy example: if a car on a ramp starts to roll, the car will begin to move faster
 Newtons 3rd Law
 for every action, there is an equal and opposite reaction
 Newton’s 2nd Law
 the greater the mass of the mass of the object being accelerated, the greater the amount of force is need to accelerate the object