Question

Mrs. Mac’s class has been assigned a lab. The purpose of the lab is to determine the influence of various surface types on a wooden block . Throughout the course of the lab, they drag the same block across various surfaces and measure the force of friction.
What are the constants?
What is the independent variable in the experiment?
What is the dependent variable?

Answer 1

Constants (kept the same):
- the wooden block (same block, so same mass and contact area)
- the block’s weight/normal force
- the way it’s dragged (same pull angle, same method, same measuring device)
- other conditions like the person doing the pulling, speed/velocity if controlled, and room conditions

Independent variable:
- the surface type (the different surfaces the block is dragged across)

Dependent variable:
- the force of friction measured (frictional force, e.g., kinetic friction)