Experimental Design and Variables

The video tutorial covers essential topics for the midterm, focusing on the scientific method and lab skills. It explains the roles of independent and dependent variables in experiments, using the 'Making Connections' lab as an example. The tutorial also discusses ways to improve experiment validity through repetition and increasing sample size. Additionally, it provides guidance on using scientific tools like graduated cylinders and rulers. The video concludes with a review of questions related to the scientific method and measurement techniques.

What is the first step in setting up a scientific experiment?

• Collecting data

• Identifying variables

• Formulating a conclusion

• Conducting a trial

In an experiment, what is the role of the independent variable?

• It is the data collected

• It is the result of the experiment

• It is the variable that remains constant

• It is the variable that is changed

What was the independent variable in the 'making connections' lab?

• Resting time

• Type of clothespin

• Amount of exercise

• Number of clothespin squeezes

Which group receives the normal treatment in an experiment?

• Experimental group

• Variable group

• Sample group

• Control group

How can the validity of an experiment be increased?

• By changing the hypothesis

• By repeating the experiment

• By reducing the sample size

• By altering the control group

What is the lowest point of a liquid in a graduated cylinder called?

• Base

• Meniscus

• Bottom line

• Zero mark

When measuring with a ruler, why is it important to note the starting point?

• To use the correct tool

• To measure faster

• To avoid errors in units

• To ensure accuracy

Why is it important to check pulse rate before and after exercise in an experiment?

• To serve as a conclusion

• To justify sample size

• To establish a baseline for comparison

• To formulate a hypothesis

In an experiment testing exercise's effect on clothespin squeezes, what is the dependent variable?

• Type of exercise

• Number of squeezes

• Amount of exercise

• Duration of rest

What is the purpose of having a control group in an experiment?

• To test multiple variables

• To provide a baseline for comparison

• To increase the sample size

• To change the outcome