[SEC 3] CHAPTER 1 - physical quantities Flashcards
length
SI unit: metre
SI unit symbol: m
mass
SI unit: kilogram
SI unit symbol: kg
time
SI unit: second
SI unit symbol: s
thermodynamic temperature
SI unit: kelvin
SI unit symbol: K
electric current
SI unit: ampere
SI unit symbol: A
amount of substance
SI unit: mole
SI unit symbol: mol
name all scalar quantities
- distance
- speed
- mass
- time
- density
- work
name all vector quantities
- displacement
- velocity
- weight
- force
- acceleration
- moment
measuring tape
range of measurement: 0-5m
precision: 0.1cm
metre rule
range of measurement: 0-1m
precision: 0.1cm
digital calipers
range of measurement: 0-15cm
precision: 0.001cm
digital micrometer screw gauge
range of measurement: 0-2.5cm
precision: 0.001mm
what is time taken for one complete oscillation and what is the formula?
period
T
formula: T = 1/T
1 oscillation takes how much time
1 osc = how many seconds
what is the number of oscillations in 1 second and what is the formula?
frequency
f
how many oscillation produced in 1 sec
1 sec = how many osc
why should timing recordings using digital stopwatch be recorded in 0.1 sec?
because of human reaction time in stopping and starting stopwatches, typically in the range of 0.3-0.5 seconds, introduces random error in the timing
why need to time for 20 osc to find period instead of taking for 1 osc?
this is to reduce the percentage of the human reaction time error in the readings
