Describing Experiments Flashcards
What are reliable results
Results where there is lots of the same data
What are accurate results
Correct results
What are valid results
Results that are both reliable and come from experiments that were designed to be a fair test
What is a variable
Something that has the potential to change
In an experiment how many variables do you usually change
1
How do you make something a fair test
Keep everything bar 1 thing the same
What is the independent variable
The variable you change
What is the dependent variable
The variable you measure
What is the control variable
The variable you keep the same
How do you improve the reliability of an experiment
Repeat 3 times and find the mean
Hazard of radioactivity
Too much exposure can damage skin cells
Hazard of springs
Spring can snap so protect your eyes
Hazard of electricity
You can get electrocuted so stay away from water
How can you make an experiment more accurate if you are timing something
Use a stopwatch
How can you measure a lengthin a more precise way
Use a ruler with millimetres
Increase the number of decimal places used
If you’re calculating an ___________, then ignore any anomalous results
Average
If the independent variable is categoric then you should use a _______ ________ to display the data
Bar chart
If the independent variable is continuous then you should use a ________ ________ to display the data
Line graph
What is categoric data
Comes in distinct categories (e.g colours, metals)
What is continuous data
Can come in any value within a range (e.g length, volume, time)
In a line graph, the dependent variable goes on the ___-axis
y-axis
In a line graph, the independent variable goes on the ___-axis
x-axis
Make sure you fill at least ______ of the space that you’re given to draw a graph
Half
If you’re told to join up the points using a straight line, use a _________ to draw a neat line between each point
Ruler
If you’re told to draw a line of best fit, try to draw the line through or as near to as many points as possible ignoring _____________ results
Anomolous
When plotting points, use a sharp pencil and make a neat little _________ (don’t do blobs)
Cross
A graph is used to show the relationship between two ____________ - you need to be able to describe this. E.g. the graph shows that as the voltage increases, so does the current
Variables
When reading information off a graph you must draw a _____________ line up from the __-axis and a ______________ line across to the __-axis
Veritcal
x-axis
Horizontal
y-axis
Name 5 things you should do when describing planning an experiment
- Say what you’re measuring (dependent variable)
- Say what you’re changing (independent variable)
- Describe the method
- Describe the apparatus used
- Describe what variables you’re keeping constant
- Say that you will repeat the experiment 3 times to make it more reliable
What should you do when asked to evaluate a conclusion
Say whether or not you think that evidence from the experiment supports the conclusion and why
