Building a Spring Scale (Elba Lopez)

Elba Lopez, Nueva Esperanza Charter Academy

NGSS Engineering Standards

Disciplinary Core Ideas

MS-PS2-4. Construct and present arguments using evidence to support the claim that gravitational interactions are attractive and depend on the masses of interacting objects.[Clarification Statement: Examples of evidence for arguments could include data generated from simulations or digital tools; and charts displaying mass, strength of interaction, distance from the Sun, and orbital periods of objects within the solar system.] [Assessment Boundary: Assessment does not include Newton’s Law of Gravitation or Kepler’s Laws.]

Science and Engineering Practices:

• Asking questions and defining problems

• Planning out and carrying out investigations

Crosscutting concepts:

• Cause and Effect

  • Cause and effect relationships may be used to predict phenomena in natural or designed systems. (MS-PS2-3),(MS-PS2-5)

• Systems and System Models

  • Models can be used to represent systems and their interactions—such as inputs, processes and outputs—and energy and matter flows within systems. (MS-PS2-1),(MS-PS2-4)

Materials needed

Ruler, rubber bands or Slinky, String, paper cup, pencil, paper,objects to weigh

Procedure

1. Place a ruler on the edge of a table or desk so that it extends past the edge. Stack a heavy object on the ruler to hold it down securely.

2. Loop several rubber bands together to create a "string of rubber bands". (picture)

3. Loop the end of one rubber band to the end of the ruler extending over the edge of the tabletop.

4. Punch holes in opposite sides of a paper cup (top, near the rim) (5oz) (picture)

5. Tie each end of a short piece of string (15-20 cm) to each of the holes, making a string handle for the cup.

6. Hang the string handle onto the last rubber band on the " rubber band string".(picture)

7. Tape a sheet of plain white paper to the side of the table or desk near the bottom of the cup.

8. Tape pencil to the underside of the cup so that the point faces the paper

9. Using a marker, make a short, horizontal line on the paper at the place that the pencil is pointing to, and label it "0."

10. Drop a light object of known mass into the cup. Make a line to show the pencil's new position and label it "1.

11. Measure and record the distance between marks.

12. One by one, drop up several objects into the cup. For each object, mark the new position of the pencil and label the mark with the number of objects.

Questions

• Inculde at least three questons (with answers) that you can ask to assess understanding of the principles ilustrated

Photos

• Photos of Engineering Project

• Photos of real-life application of engineering Concepts