How do I generate a hypothesis?
I have to do a lab on the effect of smoking on respiratory rate by comparing smokers to non-smokers, my independent variables are the smokers and non-smokers and the dependent variable is the respiratory volume.
What would be the hypothesis relating the two?
A hypothesis is a proposed outcome of an experiment. It can use preliminary knowledge about the topic to help predict the outcome of an experiment but it should be developed and written before the actual experiment is done.
Thinking about the independent and dependent variables is a great place to start. Since you are measuring the respiratory volume of two groups, your hypothesis should include something that compares the two groups (i.e. one is higher/lower). As supporting information for your hypothesis, you should probably also define what is considered a smoker vs. non-smoker (i.e. smoked for more than a year, smoke a pack a day, etc).
We want to phrase the hypothesis as a direct statement such as
The hypothesis is that the respiratory volume of smokers will be ________ than that of non-smokers. A smoker is someone who ...