# Pass the Water

 Materials: Baking Dish, Water, Space Time Allotment: 3 Class Days

### Purpose:

The purpose of this activity is to investigate the concept of inertia and to extend it to a discussion of automobile safety practices.

### Procedure:

1. Acquire a baking dish and fill it to the rim with water.
2. Find a wide, flat area which can be used to move around in; outside in the yard would be ideal. Regardless of the location, the location must be an area which can get wet (do not do this lab on your living room carpet; and if unsure of the location, first ask a parent).
3. Hold the pan of water level, and walk about in the area. As you walk, make careful observations of the water and of your tendency to be more or less careful of spilling it at various locations. If you spill a significant amount of water at any time, then refill the water to the rim. Your walking should include the various types of motion:
• Starting with the water at rest on top of a table, abruptly accelerate the water to a high speed in a short amount of time.
• Walk with a constant speed in a straight line for at least 20 feet.
• After walking for a given distance in a straight line, make an abrupt right-hand turn; repeat this procedure for a abrupt left-hand turn.
• After walking some given distance in a straight line at a moderate speed, abruptly stop.

### Observations:

State Newton's First Law of Motion:

Define inertia:

Record observations for the following types of motion. In your observations, comment on what the water did during the motion and comment on your tendency to be more or less careful when you made the particular motion. Your descriptions should be clear.

1. Starting with the water at rest on top of a table, abruptly accelerate the water to a high speed in a short amount of time.

2. Walk with a constant speed in a straight line for at least 20 feet.

3. After walking for a given distance in a straight line, make an abrupt right-hand turn; repeat this procedure for a abrupt left-hand turn.

4. After walking some given distance in a straight line at a moderate speed, abruptly stop.

### Conclusion:

Explain how your observations in this lab demonstrate Newton's law of inertia. Be specific and use examples. Do a bang-up job!

### Extension:

There are a variety of phenomenon which occur in an automobile which illustrate in some manner Newton's law of inertia. Identify and describe at least two phenomenon which illustrate Newon's law of inertia. Use specifics to clearly explain how the phenomena which you describe illustrate Newton's first law.