How Science Works Flashcards
What is a hypothesis? (science)
An explanation for what scientists have observed
Describe the stages involved in the ‘scientific method’.
- Coming up with a hypothesis.
- Testing the hypothesis.
- If all evidence supports it, the hypothesis is accepted for now. Theories never become total undisputable fact as new evidence may come about that contradicts the hypothesis.
- A model may be made to explain the theory more simply e.g. representational model or computational model.
Why is it important to tell people about scientific dicorveries?
So the public can modify their habits if they need to or so that they are aware of the benefits of different scientific methods.
What problems are associated with the communication of scientific ideas?
They may be presented in a biased way.
Reports in the newspaper or on television are not peer-reviewed. This means that some data may be over-simplified, inacurate or interpreted incorrectly
Scientists can’t provide the perfect answer to ethical questions. Why?
There are always different opinions within ethical debates so one scientist may say that a certain procedure is ethically acceptable but another scientist may disagree.
What is a hazard? (science)
Something that could potentially cause harm
What is a risk? (science)
The chance that a hazard will cause harm. Something ‘high risk’ has a higher chance of causing harm.
Give three examples of hazzards you may encounter when carrying out an experiment. How would you reduce the risk?
Chemicals can burn your skin so wearing goggles and gloves when handling chemicals (eg. sulfuric acid) can reduce the risk.
Fire. An unattended bunsen burner is a fire hazard. To reduce risk, ensure that the bunsen is always being closely watched by at least one person and also place the bunsen on a heat proof mat.
Microorganisms. Some bacteria can make you ill. To reduce this risk, ensure that everyone who takes part in or does the experiment, thoughroughly washes their hands after the experiment.
Why is a larger sample size better than a smaller sample size?
It gives a more rounded and fair representation of the data.
How can you improve the accuracy of results to an experiment?
Repeat results several times and take an average.
Compare results with other people’s results.
Video the experiment (if you’re measuring something visible) so that you can go over the experiment in more detail.
Ensure you’re using the correct equipment in the correct way.
What does the term precise mean? (science)
All data is really close to the mean.
What type of errors are there and how are they caused? (science)
RANDOM ERROR: this is human error in measuring. You can reduce this by taking repeat readings and finding a mean. This makes results more precise.
SYSTEMATIC ERROR: this is when certain things are done incorrectly eg. reading from the end of the ruler not from the 0.
ZERO ERROR: casued by equipment not being zeroed properly eg. a mass balance measuring 1g before anything is put on it.
What is an anomylous result?
When a result doesn’t fit in with the rest.
How can you make an investigation fair? What are the different types of variable?
Control the variabes.
The variable you change is called the independent variable.
The variable you measure is the dependent variable.
The variable you keep the same are the control variables.
what does it mean to make the evidence repeatable?
If the same person carried out the experiment using the same method and equipment, the results would be similar
