Measurements

Question 1

accuracy vs precision

Answer 1

Accuracy measures how close results are to the true or known value.

Precision, on the other hand, measures how close results are to one another.

Question 1

Rules for addition, subtraction and averaging multiple quantities into a single representative value

Answer 1

Express to smallest decimal place

Question 2

Rules for multiplication, division and averaging of a quantity into multiple equal parts

Answer 2

Express to smallest significant factor(S.f.)

Question 3

Random error definition

Answer 3

Error that gives rise to a scatter of readings about a mean value

Question 4

Random error remedy

Answer 4

Reduce by taking the average of multiple readings

Question 5

Constant error definition

Answer 5

Error that leads to readings that are consistently more or consistently less than the actual reading

Question 6

Constant error remedy

Answer 6

Eliminate by identifying and removing the source

Question 7

factor (x10^?)
nano
micro
milli
centi
deci
kilo
mega
giga
tera

Answer 7

factor
10 ^-9
10 ^-6
10 ^-3
10 ^-2
10 ^-1
10 ^3
10 ^6
10 ^9
10 ^12

Question 8

symbols
nano
micro
milli
centi
deci
kilo
mega
giga
tera

Answer 8

symbols
n
µ(mew)
m
c
d
k
M
G
T

Question 9

what is a period, T

Answer 9

time taken for one complete oscillation

Question 10

what is frequency, f

Answer 10

number of oscillations in 1 second, hence f = 1/T

Question 11

period(T) of a pendulum is governed by what equation

Answer 11

T = 2π√l/g
l is length of the pendulum string
g is the gravitational acceleration of the planet

Question 12

what to use to measure distances longer than 1 metre

Answer 12

tape measure

Question 13

what to use to measure up to 1 metre

Answer 13

metre rule

Question 14

what to use to measure up to 0.01mm with a max rang of 15cm

Answer 14

vernier calipers

Question 15

what to use to measure up to 0.001mm with a max range of 2.5cm

Answer 15

micrometer screw gauge

Question 16

how to determine uncertainty

Answer 16

Each (physical) measurement you make has an error of a half a division. so the uncertainty is half the smallest measurement
e.g. a protractor’s smallest measurement is 1deg, so its uncertainty is 0.5deg

Question 17

graph guide
STAPLE

Answer 17

Scale -> 3/4 the graph paper
Title -> graph of <y>(dependent) against <x>(independent)
Axes -> label diagram axes with symbol(t) units(s)
Points -> mark with x
Link -> use a ruler to draw to y axis
Evidence -> GRADIENT(rise over run) Y-INTERCEPT(draw to y-axis) EXTRAPOLATION (planm ahead)</x></y>