Examlex
A helicopter stays aloft by pushing large quantities of air downward every second.What mass of air must be pushed downward at 40.0 m/s every second to keep a 1 000-kg helicopter aloft?
Double-blind Study
A scientific experiment where both the participants and the researchers do not know who receives the treatment or the placebo, eliminating bias.
Survey Research
A research method involving the collection of information from a sample of individuals through their responses to questions.
Independent Variables
are variables in an experiment that are manipulated by the researcher to observe their effect on dependent variables, crucial for establishing causal relationships.
Convenience Sample
A type of non-random sampling where participants are selected based on their availability and willingness to take part.
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