3.1: Measurements And Their Errors Flashcards
What is the units for Mass (1)
kg (kilograms)
What is the units for Length (1)
m (metres)
What is the units for Time (1)
s (seconds)
What is the units for the Amount of substance (1)
mol (moles)
What is the units for Temperature (1)
K (kelvin)
What is the units for Electric current (1)
A (amperes)
What is the multiplier for prefix Tera(1)
T, 10^12
What is the multiplier for prefix Giga (1)
G, 10^9
What is the multiplier for prefix Mega (1)
M, 10^6
What is the multiplier for prefix Kilo (1)
k, 10^3
What is the multiplier for prefix Centi (1)
c, 10^-2
What is the multiplier for prefix Milli (1)
m, 10^-3
What is the multiplier for prefix Micro (1)
µ, 10^-6
What is the multiplier for prefix Nano (1)
n, 10^-9
What is the multiplier for prefix Pico (1)
p, 10^-12
What is the multiplier for prefix Femto (1)
f, 10^-15
What are Random errors (1)
Errors that affect precision and cause a spread about the mean. You cant get rid of them all
How to reduce random errors (1)
Repeat and calculate a mean
What are Systematic errors (1)
Errors that affect accuracy and cause all results to be too high or too low by the same amount each time.
What causes systematic errors (2)
the method used , the apparatus used
How to reduce systematic error (1)
calibrate apparatus by measuring a known value, if reading is inaccurate systematic error can be identified easily
What is Zero error (1)
A type of systematic error that occurs when a balance is not zeroed correctly.
What is Parallax error (1)
A type of systematic error that occurs when reading a scale at a different angle.
What is Precision (2)
Precise measurements are consistent, they fluctuate slightly about a mean value
What is Repeatability (1)
If the original experimenter can redo the experiment with the same equipment and method then get the same results it is repeatable.
What is Reproducibility (1)
If the experiment is redone by a different person or with different techniques and equipment and the same results are found, it is reproducible.
What is Resolution (1)
The smallest change in the quantity being measured that gives a recognisable change in reading.
What is Accuracy (1)
A measurement close to the true value
How could u Reduce percenatage Uncertainty (1)
you can measure larger quantities.
How to calculate Repeated Data Uncertainty (1)
range / 2
What happens to the absolute uncertainty when u add/subtract data (1)
Add the absolute uncertainties
How do u calculate Percentage Uncertainty (1)
(uncertainty/value) × 100.
What happens to the absolute uncertainty when Multiplying/Dividing Data (1)
Add the percentage uncertainties .
What happens to the absolute uncertainty when Raising to a Power (1)
Multiply the percentage uncertainty by the power
What are Error Bars (2)
shows uncertainties , line of best and worst fit must go thru all error bars
How to calculate Gradient Uncertainty (3)
draw the steepest and shallowest line of best fit, calculate their gradients, uncertainty = difference between the gradients
If the lines if best/worst fit have diff y intercepts how should u calculate the percentage uncertainty (1)
Best y intercept - worst y intercept / best y intercept x100
How should u make estimations of physical quantities (1)
- Give the estimate of an order of magnitude to the nearest power of 10
