Experiment 1: Newton’s First Law
Procedure Question:
Record your observations for each type of motion from Step 4 in the space below. Comment on where the water tended to move. If the water spilled, note which side it spilled from.
Questions:
Explain how your observations of the water demonstrate Newton’s law of inertia.
Draw a free body diagram of your box of water from the situation in Procedure 4d. Draw arrows for the force of gravity, the normal force (your hand pushing up on the box), and the stopping force (your hand decelerating the box as you stop.) What is the direction of the water’s acceleration?
*Note, free body diagrams are discussed in depth in Lab 2: Types of Forces. See Figure 3 for a sample diagram. Remember, the object is usually indicated as a box, and each force that acts upon the box is indicated with an arrow. The size of the arrow indicates the magnitude of the force, and the direction of the arrow indicates the direction which the force is acting. Each arrow should be labeled to identify the type of force. Note, not all objects have four forces acting upon them.
Ffriction
Fapp
Fnormal
Fgravity
Figure 3
Figure 3: Sample FBD
Can you think of an instance when you are driving or riding in a car that is similar to this experiment? Describe two instances where you feel forces in a car in terms of inertia.
