Physical Quantities Flashcards
What are the six base quantities(in our syllabus)
mass, length, time, amount of substance, temperature, electric current
State prefixes for magnitude in order from biggest to smallest
tera, giga, mega, kilo, deci, centi, milli, micro, nano
What is the estimate for diameter of earth
10^7 m
What is the estimate for width of human hair
10^-4 m
What should measurements be recorded to for digital calipers
0.01cm
What should measurements be recorded to digital micrometer screw gauge
0.001cm
How to avoid parallax errors
Eye should be positioned such that our line of sight is perpendicular to the mark on the scale
How to prevent zero error
Digital calipers/micrometer screw gauge must be reset to zero before measurements are taken
How to prevent over tightening of digital micrometer screw gauge
Turn the thimble until anvil and spindle gently touch the object, turn rachet until it clicks once.
Use of locking screw in digital calipers
To ensure jaws do not move apart
How to record time for stopwatch and why
Record to nearest 0.1s to account for uncertainty due to human reaction time.
Why is recording time for more oscillations of pendulum to obtain period more accurate than recording time for one oscillation
First method gives a smaller proportion of the same human reaction time in the result
