physical quantities and base units

what is distance

length along the actual path travelled from start to finish

is distance vector or scalar

scalar

is displacement scalar or vector

vector

what does displacement and distance both measure

how far an object moved

what units do they use for distance and displacement

metres or m

what is speed

rate of change of distance

is speed scalar or vector

scalar

what is velocity

rate of change of displacement

what is the formula of speed

distance travelled / time taken

what is the formula of velocity

displacement / time taken

is velocity scalar or vector

vector

what is the unit for both speed and velocity

ms^-1

what is acceleration

rate of change of velocity

what is the formula of acceleration

change in velocity / time taken

what is the unit of acceleration

ms ^-2

what can cause acceleration

change in speed or change in direction

what happens when an object is slowing down

negative velocity

what is negative velocity

deceleration or negative acceleration

what are derived units

combining the units in a defining equation

what are the derived units for density

kg m^-3

what are the derived units for momentum

kg m s^-1

what are the derived units for force

kg m s^-2

what are the derived units for pressure

kg m² s^-2

what are the derived units for work

kg m² s^-2

what are the derived units for power

kg m² s^-3

what are the derived units for electrical charge

A s

what are the derived units for potential difference

kg m² A^-1 s^-3

what are the derived units for resistance

kg m² A^-2 s^-3

what is the special name for force

newton N

what is the special name for pressure

pascal Pa

what is the special name for work

joule J

what is the special name for power

watt W

what is the special name for electrical charge

coulomb C

what is the special name for potential difference

volt V

what is the special name for resistance

ohm Ω

what does homogeneous mean in this topic

composed of identical parts

why is being able to find homogeneity of equations good

it can be particularly useful after you have rearrange and equation

is a homogeneous equation correct

could be but doesn’t prove it

what does homogeneity of equations mean

base units of each part must be the same

what does the symbol T represent

tera

what does the symbol G represent

giga

what does the symbol M represent

mega

what does the symbol k represent

kilo

what does the symbol d represent

deci

what does the symbol c represent

centi

what does the symbol m represent

milli

what does the symbol μ represent

micro

what does the symbol n represent

nano

what does the symbol p represent

pico

what does the symbol f represent

femto

how much is a (what is its multiplier) for tera

10^12

how much is a (what is its multiplier) for giga

10^9

how much is a (what is its multiplier) for mega

10^6

how much is a (what is its multiplier) for kilo

10³

how much is a (what is its multiplier) for deci

10^-1

how much is a (what is its multiplier) for centi

10^-2

how much is a (what is its multiplier) for milli

10^-3

how much is a (what is its multiplier) for micro

10^-6

how much is a (what is its multiplier) for nano

10^-9

how much is a (what is its multiplier) for pico

10^-12

how much is a (what is its multiplier) for femto

10^-15

where do numbers and base units come in place

pure numbers do not have base units

what is the difference of 5m and 5.00m

5.00m is more accurate because it has more significant figures and is to the nearest centimetre

if your raw data is all 4 significant figures, how do you give your answer

4 significant figures

what is 4.62 in 1 significant figure

5

what is 0.00501 in 2 significant figures

0.0050

what is 3 × 10^8 in 3 significant figures

3.00 × 10^8

what is 169 in 2 significant figures

1.7 × 10²

what is a vector

a quantity with size(magnitude) and direction

what is a scalar

a quantity with size(magnitude) and no direction

scalar or vector? discance

scalar

scalar or vector? speed

scalar

scalar or vector? mass

scalar

scalar or vector? displacement

vector

scalar or vector? velocity

vector

scalar or vector? weight

vector

scalar or vector? pressure

scalar

scalar or vector? force

vector

scalar or vector? energy

scalar

scalar or vector? temperature

scalar

scalar or vector? momentum

vectors

scalar or vector? acceleration

vector

scalar or vector? volume

scalar

scalar or vector? electric current

vector

scalar or vector? torque

vector

scalar or vector? density

density

how can vectors be represented

length and direction of an arrow on a drawing

why can 4N + 4N give you 0N and/or 8N

force is a vector and adding them depends on direction of force

how do you add vectors on the same direction

simple F1 + F2

how do you add vectors going opposite direction

take one as positive and the other as negative and just add

how do you find the resultant of two vectors at 90 degree to each other

draw adjacent sides of a rectangle

what is the resultant on a 90 degree vector drawing

the diagonal

how do you find the magnitude of a 90 degree vector drawing

Pythagoras’ theorem

what d o you do when subtracting vectors

make one vector positive and the other negative

what do vector subtraction have in common with vector addition

when it is the same size acting in the opposite direction

how do you calculate the resultant of an object being acted on by more than two vectors

draw each vector head to tail until you get a shape. Draw a line from start to end point; that is your resultant

what is the resultant on a vector triangle

third side of a vector

what could you use to find the resultant of a vector triangle when Pythagoras doesn’t work

trigonometry, cosine rule, sine rule

what is a physical quantity

feature of something which can be measured

what are orders of magnitude of quantities

expressing its size or scale in powers of 10