Date: January 31, 2000

Grade Level(s): 11, 12

Subject(s):

• Science/Physics
• Science/Space Sciences

Description: A basic first look at gravity. How it is measured.

Goals: The students will understand the basic interaction between two massive bodies.

Objectives: The students will be able to scientifically explain why the human body is attracted by the Earth

Materials:

• ball bearings
• marker
• hoop
• jar
• meter stick
• vacuum cylinder containing a penny and a feather, and at least one computer

Activities:

1. Demonstration: Two ball bearings will be dropped off the edge of a table. One will be dropped straight down from the edge, and the other one will be given a slight horizontal push. Both balls will hit the ground at the same time.
2. Experiment: The students will be given a meter stick with pre-measured reaction lines. They will then measure each other's reaction time.
3. Experiment: Set up a marker on a hoop balanced on a jar. The student will pull the hoop out and the marker will drop into the jar.
4. Demonstration: Show that in a vacuum cylinder a feather and stone fall with the same acceleration.
5. Computer activity: Using one large computer at the front of the room, teacher goes to the website: http://www.pitt.edu/~dwilley/hdatltwmenu.html .
Choose the link Energy and Pressure. Then, choose the link Bed of Nails. Discuss how the force of gravity is utilized in the art of laying on the bed of nails.

Activities:

1. Demonstration: Two ball bearings will be dropped off the edge of a table. One will be dropped straight down from the edge, and the other one will be given a slight horizontal push. Both balls will hit the ground at the same time.
2. Experiment: The students will be given a meter stick with pre-measured reaction lines. They will then measure each other's reaction time.
3. Experiment: Set up a marker on a hoop balanced on a jar. The student will pull the hoop out and the marker will drop into the jar.
4. Demonstration: Show that in a vacuum cylinder a feather and stone fall with the same acceleration.
5. Computer activity: One student per computer, have the students go to the website: http://www.pitt.edu/~dwilley/hdatltwmenu.html . Have the students choose a link. Since the rest of the Unit also deals with heat radiation, fluid pressure, and superconductivity; the students can choose any of the links and present the material in their own way on the last two days of the unit.

Activities:

1. Demonstration: Two ball bearings will be dropped off the edge of a table. One will be dropped straight down from the edge, and the other one will be given a slight horizontal push. Both balls will hit the ground at the same time.
2. Experiment: The students will be given a meter stick with pre-measured reaction lines. They will then measure each other's reaction time.
3. Experiment: Set up a marker on a hoop balanced on a jar. The student will pull the hoop out and the marker will drop into the jar.
4. Demonstration: Show that in a vacuum cylinder a feather and stone fall with the same acceleration.
5. Computer activity: With four students assigned to each computer, have the students go to the website: http://www.pitt.edu/~dwilley/hdatltwmenu.html . Have the students choose a link. Since the rest of the Unit also deals with heat radiation, fluid pressure, and superconductivity; the students can choose any of the links and present the material in their own way on the last two days of the unit.

Assessment:

1. Teacher will walk around and make sure none of the equipment is being misused.
2. Have lab handouts for the students to complete during the labs.
3. Grading lab sheet and participation in the lab.