Physics 11 Exam

exact values

when you count objects

when there is an exact conversion (ex: 1 foot = 12 inches)

- infinite sig figs

measured values

obtained from measuring tools

scalar quantity

magnitude only

-distance

vector quantity

direction and magnitude

- distance and [direction]

displacement

distance from the starting point to final point

- doesn't depend on path

displacement = final distance - initial distance

slope of P-T graphs

slope = rise/run

= velocity (m/s)

average velocity

displacement (with an arrow) / time

instantaneous velocity

find the slope at a specific point

area under V-T graphs

= displacement

acceleration

rate of change of velocity

downward acceleration is due to

force of gravity

g constant value

9.80m/s [down]

gravitational force

force of attraction between earth + objects near/on its surface, as well as anything with mass

force

- push or pull on an object

- measured in Newtons (N)

gravitational force

an attractive force that acts between any two objects

mass

quantity of matter in an object

weight

force of gravity acting on an object

newtons law of universal gravitation

- the magnitude of Fg is directly proportional to the product of masses

- the magnitude of Fg is inversely proportional to the square of the objects' distance

G constant

6.67x10^-11

inertia

resistance to change in motion

newtons first law of motion

an object in motion will remain in motion unless acted upon by another force

- moving objects will eventually stop without external forces

newtons second law of motion

if there is a net external force, the object will accelerate

- acceleration is proportional to net force

- acceleration is inversely proportional to mass

newtons third law of motion

action reaction pair

friction

- static friction: prevents an object from starting to move

- kinetic friction: force that acts when 2 objects slide

work

measure of energy transfer when an object is moved by an applied force

positive and negative work

POS: Force and displacement are in the same direction

zero work

When force & displacement are perpendicular

law of conservation of energy

- total amount of energy never changes

- energy cannot be created or destroyed

- energy that exists can only be changed from one form to another

- no energy is ever lost

Power

the rate at which work is done

- Si unit = W (watts)

energy consumption

the conversion of produced/stored energy into heat

kinetic molecular theory of matter

- particles are always vibrating and rotating

- vibrations are motions within/between particales that increase and decrease distance between particles

thermal energy

- depends on mass, temp, and state of matter

- is internal energy associated with movement and interactions of particles

temperature

measure of average kinetic energy of particles of a substance

- more kinetic energy > more movement > higher temp

temperature scales

0 C = 273K

latent heat

thermal energy needed for a phase change

latent heat of fusion and specific latent heat of fusion

- thermal energy transferred when phase change from SOLID > LIQUID

- SPECIFIC: thermal energy needed to melt 1kg of substance at its melting point

heat capacity and specific heat capacity

amount of thermal energy needed to change the temp of an object by 1K or 1C

principle of thermal energy exchange

when two substances at different temperatures are mixed, thermal energy lost by hotter substance = thermal energy gained by colder substance

electrical circuit

- source of electrical energy, conductor, and load (converts energy into light, heat, sound)

series circuits

A current that has only one path therefore is constant at all points

parallel circuit

A circuit that contains more than one path for current flow.

- potential difference is the same at all points