Science Unit 4 Test - Lecture notes unit 4 PDF

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Science Unit 4 Test...

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Science Unit 4 Test Energy Types of energy           Etc….

Heat Light Electricity Kinetic Solar/wind/geothermal/nuclear/hydraulic Chemical Nuclear Mechanical Sound Potential

Energy input/output  

Input: type and amount of energy going into something Output: type and emount of energy exiting something

EXAMPLE:

Law of conservation of energy  

Energy can’t be created or destroyed, only transferred or transformed Total amount of energy in an isolated system= constant

Energy transformation/transfer  

Transfer: Movement of energy from one place to the other Transformation: Changing of one form of energy to another

Energy efficiency

 

some energy is lost  the amount of energy used ( % )

Heat energy Heat and temperature    

heat= energy temperature= measure of the degree of particles (movement)  heat depends on temperature (how fast the particles are moving) energy contained in particles= thermal energy

Specific heat capacity   

heat required to raise the temp. of 1g of a substance by 1oC diff. substances have diff. heat capacities J/goC

**change in temp= Tf/TI Mechanical energy 

Made up of kinetic and potential energy

 Em= EP + EK **if potential energy decreases, kinetic energy increases Kinetic energy  The energy an object possesses due to motion Potential energy



Energy reserve energy possessed by an object defined by its position

PE= mgh PE= gravitational potential energy (J) m= mass of object (kg) g= gravity intensity (9.8N/kg) h= height of object above surface (m)

Gravity   

Greater the masses  stronger the attraction Greater the distance weaker the attraction Earths gravitational field is 9.8N/Kg**

Mass vs Weight  

Mass (m): quantity of matter in obect (kg) (never changes) Weight (w): measure of the gravitational force acting upon an object (N) (changes on diff. planets) ** an objects weight varies depending upon where it is found due to differences in gravity Weight Fg= m x g Fg= gravitational force (N) m= mass (kg)

g= grav. Field intensity (N/kg)  9.8N/kg

Forces

  

Force is show by an arrow Must point in the direction of the force and points away from object its acting on Larger forces= larger arrows

Effective force 

Force component that alters the motion of an object  parallel to the movement (Fll)



Unit= N

Work   

The transfer of energy from one place to another Work= force causes something to move Energy is consumed

W= Fll x d w= work (J) d= distance (m) Fll= effective force (N) Trigonometry SOH – CAH – TOA 1. pulling an object on a surface (CAH) 2. object sliding down a plane (use similar triangles to recreate it) (SIN)...