# 3-ps2-2 motion and stability: forces and interactions

```OKLAHOMA ACADEMIC STANDARD FOR SCIENCE:
3-PS2-2 MOTION AND STABILITY: FORCES AND INTERACTIONS
OBJECTIVE:
Students who demonstrate understanding can make observations and/or measurements of the object’s motion to
provide evidence that a pattern can be used to predict future motion. (Connected to 3-PS2-1.)
CORE IDEAS:
1. The patterns of an object’s motion in various situations can be observed and measured; when that past motion
exhibits a regular pattern, future motion can be predicted from it.
Note: Technical terms, such as magnitude, velocity, momentum and vector quantity are not introduced at this
level, but the concept that some quantities need both size and direction to be described is developed.
ASSESSMENT BOUNDARY:
•
Assessment does not include technical terms such as period, frequency, magnitude, velocity, momentum and
vector quantity.
MATERIALS REQUIRED:
•
Gravitate Kit
o
o
o
2 rubber hoses
Braces
Legs
•
Measuring Tape
•
Balls of varying sizes and weights
•
Scale (for weighing balls)
•
Stopwatch
3-PS2-2: Motion and Stability: Forces and Interactions
PREPARATION:
1. Set up the track.
2. Measure and record the length L.
_____m
3. Measure and record the height H.
_____m
4. Measure and record the mass of the
ball or moving object. _____kg
PROCEDURE:
Core Idea #1: The patterns of an object’s motion in various situations can be observed and measured. When
that past motion exhibits a regular pattern, future motion can be predicted from it.
1. Place the ball at the top of the track and release it. If the top of the track is flat, you may need to give the ball a
gentle push.
a. Repeat this step several times to allow the students to observe patterns.
b. Ask the students to list the patterns they observe.
2. Ask the students to predict the ball’s travel pattern under various circumstances.
a. Does the ball always complete the loop?
b. Does the ball go past the end of the track?
c. If you use greater force will the ball complete the loop? Will it travel farther past the end of the track?
Measure the distance.
d. If you use lesser force will the ball complete the loop? Will it travel past the end of the track? Measure the
distance.
e. If you make changes to the height or angle of the track will it affect the ball’s travel? How?
Assess: Ask questions to help the students identify how various forces impact the ball’s travel pattern.
2
```