
energy
something that is need to make things happen. Energy is the ablitiy to do work

Basic yet important energy points (5)
 Energy cannot be created to destroyed
 All living things have and need energy
 energy existis in different forms
 energy canchange forms
 Energy is not a substancew it does not take up space and cannot be weighed

Measuring energy
Energy is measured in joules. Joules is a very small unit so kilo joules are offen used. the symbol is J or kJ

Two main forms of energy
Potential energy (stored energy) and active energy

Potential energy types
 Gravitational
 elastic
 nuclear
 chemical
 magnetic
 (GENCM)

Active energy types
 Sound
 heat
 radiant (light)
 eletrical
 kinetic
 (SHERK)

Law of conservational energy
Energy cannot be created or destroyed it only changes from on form to another. The total out put remains constant as the input

Weight
Force pf gravity pullling towards the earth. It is gravity times mass


Measuring forces
Force is measued in newetons

Four types of forces
Lift, gravity, thrust, and friction

Un/balenced forces
 when forces sre balence the object is stationary or traveling at a constanst speed
 When forces are unbalenced the oject is acclerating or decelerating

Net force
When net force is 0 the forces are balenced. When net force isn't 0 the forces are unbalenced

Calculating net force/resulant force
 If forces are acting in the same direction you add them together
 If the forces are acting in the opposite then we subtract the the bigger value from the smaller
 the object will move in the direction of the bigger force

Distance time graphs
 Distance on yaxis, time on xaxis
 Constant upwards slope means travelling at a constant speed
 Straight line means stationary
 curving upward means accerating
 curving downwards means decellerating
 downwards slope means returning to start
 slope is speed, rise over run

Speed time graph
 speed yaxis, time on xaxis
 upwards slope  accerating
 downwards slope  declerating
 horizontal on base  stoped
 horizontal in air constant speed
 total distance is area under the line

Accleration due to gravity
when an object falls verically it accerates due to gravity. This accerationna of a free falling object is called acceration due to gravity. This acceration due to gravity has a value of 9.8ms^{2} but in calculations it is rounded to 10ms^{2}

Terminal Velocity
when objects fall from a large height, the do not continually accerate but eventually moves at a constant speed. This is beacuse air resistance increases as speed and balences out the down wards force of gravity, and the object cannot acclerate

Discus how the speed of a car effects the damage in a crash
Kinetic energy is proportional to the square of speed when speed is doubled the kinetic energy is quadrupled by factor 4. Therefore the impact is heavier and tyhe more damage

