Measurements And Errors

Question 1

Name the six SI base quantities and their units

Answer 1

Mass (kg)
Length (m)
Time (s)
Electric current (A)
Temperature (K)
Amount of substance (mole)

Question 2

State the name, symbol and multiplying factor for each SI prefix

Answer 2

Tera (T) 1 x 10^12
Giga (G) 1 x 10^9
Mega (M) 1 x 10^6
Kilo (K) 1 x 10^3
Centi (c) 1 x 10^-2
Milli (m) 1 x 10^-3
Micro () 1 x 10^-6
Nano (n) 1 x 10^-9
Pico (p) 1 x 10^-12
Femto (f) 1 x 10^-15

Question 3

What is the uncertainty in a measurement of a quantity?

Answer 3

Difference between the measured value and the true value of the quantity

Question 4

What is the absolute uncertainty?

Answer 4

The possible difference from the true value given as a fixed number in the unit of a measurement

Question 5

What’s the percentage uncertainty of a measurement

Answer 5

Possible difference from the true value given as a percentage of the measurement

Question 6

How are uncertainties combined when measurements are added or subtracted

Answer 6

Their absolute uncertainties are added

Question 7

How are uncertainties combined when measurements are multiplied or divided

Answer 7

Percentage uncertainties are added

Question 8

How is the uncertainty found when the measurement is raised to a power

Answer 8

Uncertainty is multiplied by the power of

Question 9

What can the line of worst fit be used for

Answer 9

Finding the uncertainty in the gradient and intercepts of a straight line graph

Question 10

How can the uncertainty