units and measurements

Question 1

units of length (l/L)?

Answer 1

metres (m)

Question 2

units of mass (M/m)?

Answer 2

kilograms (kg)

Question 3

units of time (t)?

Answer 3

seconds (s)

Question 4

units of current (I)?

Answer 4

ampere (a)

Question 5

units of temperature (T/θ)?

Answer 5

kelvin (K)

Question 6

units of an amount of a substance (n)?

Answer 6

mole (mol)

Question 7

units of luminous intensity (L)?

Answer 7

candela (cd)

Question 8

the prefix of 10³?

Answer 8

kilo (k)

Question 9

the prefix of 10⁶?

Answer 9

mega (M)

Question 10

the prefix of 10⁹?

Answer 10

giga (G)

Question 11

the prefix of 10¹²?

Answer 11

tera (T)

Question 12

the prefix of 10⁻²?

Answer 12

centi (c)

Question 13

the prefix of 10⁻³?

Answer 13

milli (m)

Question 14

the prefix of 10⁻⁶?

Answer 14

micro (µ)

Question 15

the prefix of 10⁻⁹?

Answer 15

nano (n)

Question 16

the prefix of 10⁻¹²?

Answer 16

pico (p)

Question 17

the prefix of 10⁻¹⁵?

Answer 17

femto (f)

Question 18

the prefix of 10⁻¹⁸?

Answer 18

atto (a)

Question 19

what is accuracy?

Answer 19

how close a reading is to its true value

Question 20

what is precision?

Answer 20

the number of s.f a value can be measured to

Question 21

what is absolute correction?

Answer 21

the correction added to a measurement to adjust the indicated value to the true value

Question 22

what is absolute uncertainty?

Answer 22

a measure of the random error above and below the mean (given as a ±)

Question 23

what is meant by an independent variable?

Answer 23

the changed value

Question 24

what is meant by the dependent variable?

Answer 24

the measured value

Question 25

what is meant by the control variable?

Answer 25

the value that remains constant

Question 26

what is instrument precision?

Answer 26

the smallest value that can be read from a measuring instrument scale

Question 27

what is intrinsic error?

Answer 27

the contribution to a measurement’s absolute uncertainty due to an instrument precision

Question 28

what is intrinsic uncertainty?

Answer 28

the uncertainty due to the measuring instrument

Question 29

what is meant by a parallax error?

Answer 29

an error produced when not looking directly at a scale

Question 30

what is meant by a percentage uncertainty?

Answer 30

a measure of a value’s random uncertainty and its absolute uncertainty expressed as a percentage

Question 31

what is random error/uncertainty?

Answer 31

the variation in a result due to random effects in the experiment above and below the true value

Question 32

how can random error/uncertainty be reduced?

Answer 32

repeats and averaging

Question 33

what is relative correction?

Answer 33

a measure of the level of correction applied to a measurement

Question 34

what is relative error/uncertainty?

Answer 34

the ratio of the absolute error in a measurement to the value taken to be its true value

Question 35

what is meant by repeatability?

Answer 35

how close the repeat measurements are

Question 36

what is meant by reproducibility?

Answer 36

how closely the values for a specific measurement agree between different experiments

Question 37

what is a systematic error?

Answer 37

an error in the recorded results due to a fault in the experiment

Question 38

when adding/subtracting data, what do you do with the absolute uncertainties?

Answer 38

add them

Question 39

when multiplying/dividing data, what do you do with the absolute uncertainties?

Answer 39

add them

Question 40

when a measurement is raised to a power, what do you do with the uncertainty?

Answer 40

multiply the percentage uncertainty by the power