chapter 1 Flashcards
(28 cards)
difference between qualitative and quantitative data
qualitative: involves senses (touch, hear, smell, taste, sight)
usually descriptive (eg. heavy, long, fast)
quantitative: involves senses and measurements taken using instruments
usually numerical
is it qualitative or quantitative?
The fur colours of the puppy are white and brown
qualitative
is it qualitative or quantitative?
The temperature of the room is 32°C now
quantitative
is it qualitative or quantitative?
The width of the table is 82cm
quantitative
is it qualitative or quantitative?
The iron ball is heavier than the soccer ball
qualitative
what is constant variable
variables that needs to be kept constant or the same throughout the experiment to ensure a fair experiment
what does a stopwatch measure?
time
SI unit for time
seconds (s)
what does a thermometer measure?
temperature
SI unit for temperature
Kelvin (K)
what does the electronic balance measure
mass
SI unit for mass
kilograms (kg)
what does a digital calipers measure?
length
SI unit for length
metres (m)
what does a gas syringe measure
volume of gas
SI for volume
cubic metre (m³)
what does a measuring cylinder measure?
volume of liquid
what are the 2 types of errors?
zero error
parallex error
meaning of accuracy
how close the measurement is to the true value
what is zero error?
when an instrument gives a non-zero reading when the measured quantity is zero
(the balance should be at zero before able to measure things)
how to resolve zero error?
- adjust the instrument to reduce zero error
- add or subtract difference of zero error
what is parallex error?
when a person views the instrument at a wrong angle
how to resolve parallex error?
take reading at the correct angle by aligning eyes to the curve
(eg. when measuring volume of liquid using measuring cylinder or beaker, eyes should be aligned with the curve level of water)
what is precision
when you get the readings are close to one another or the same
