Physical Quantities, Units and Measurements Flashcards
what is a physical quantity?
it is a quantity that can be measured.
what does a physical quantity have?
it has a numerical magnitude and a unit.
what is the si unit for length?
metre (m)
what is the si unit for time?
second (s)
what is the si unit for mass?
kilogram (kg)
what is the si unit for temperature?
kelvin (K)
what is the operation we must use to convert a quantity from ‘prefix’ to ‘no prefix’?
multiply
what is the operation we must use to convert a quantity from ‘no prefix’ to ‘prefix’?
divide
what is the symbol and factor for giga?
10 to the power of 9; G
what is the symbol and factor of mega?
10 to the power of 6; M
what is the symbol and factor of kilo?
10 to the power of 3; k
what is the symbol and factor of deci?
10 to the power of -1; d
what is the symbol and factor of centi?
10 to the power of -2; c
what is the symbol and factor of mili?
10 to the power of -3; m
what is the symbol and factor of micro?
10 to the power of -6; (refer to symbol)
what is the factor and symbol of nano?
10 to the power of -9; n
what is the magnitude of planet earth (diameter)?
10 to the power of 7 m
what is the magnitude of moon (diameter)?
10 to the power of 6 m
what is the magnitude of height of tall mountain?
10 to the power of 3 m
what is the magnitude of length of football field?
10 to the power of 2 m
what is the magnitude of height of chair?
10 to the power of -1 m
what is the magnitude of width of paper?
10 to the power of -4 m
what is the magnitude of size of human cell?
10 to the power of -6 m
what is the magnitude of size of large molecule?
10 to the power of -9 m
what is the range and precision of a tape measure?
several cm up to a few m; 0.1cm or 1mm
what is the range and precision of metre rule?
several cm up to a metre; 0.1cm or 1mm
what is the range and precision of calipers?
several cm up to typically 10 cm (depending on caliper size); 1mm
what is the range and precision of vernier calipers?
typically 1cm to 15cm (some up to 30cm); 0.01cm or 0.1mm
what is the range and precision of micrometer screw gauge?
typically less than 2.5cm; 0.001 cm or 0.01mm
what is a pendulum used for?
it can be used to measure time after it is calibrated
what is a period?
time taken for one complete oscillation
what is a period dependant on?
the length of the pendulum
what is the relationship between the length of the pendulum and its period?
the longer the length is, the longer the period
