(5-8) A1

Science Curriculum Preview Committee Clarification of Learning Results

Revised 08/22/04

5-8

I1: Describe the motion of objects using knowledge of Newton's Laws.

Curriculum Organizing Questions

What are Newton's Laws?

How is this object moving?

Which of Newton's Laws describe the movement of this object?

Elaboration
A general exposure to Newton's Laws is all that is expected at this level.

Specific Ideas

Law 1: Every body continues in its state of rest, or of uniform motion in a straight line, unless it is compelled to change that state by forces impressed upon it.

Law 2: Force = mass x acceleration.

Law 3: To every action force there is an equal and opposite reaction force.

Developmental & Instructional Implications
The force/motion relationship can be developed more fully now and the difficult idea of inertia be given attention. Students have no trouble believing that an object at rest stays that way unless acted on by a force; they see it every day. The difficult notion is that an object in motion will continue to move unabated unless acted on by a force. Telling students to disregard their eyes will not do the trick--the things around them do appear to slow down of their own accord unless constantly pushed or pulled. The more experiences the students can have in seeing the effect of reducing friction, the easier it may be to get them to imagine the friction-equals-zero case. Benchmarks p. 90.

The early introduction of the concept of momentum in qualtitative terms prior to considering forcesis an important porposal with considerable support. Although in traditional courses this has been seen as a mathematical motion to be faced by older pupils, many studies nsuggest that we need to offer the idea of momentum so that pupils can attach to it their own idea that a moving object has something which keeps it going. ... There is a general suggestion that Newtonian ideas about motion become harder to accept as pupils become firmer in their own dynamcis. Intorducing momentum before force then allows force to be seen as that which causes a change in momentum, and it prevents the label "force' being attached to the pupils' notion of "something in the object which keeps it moving." Driver p. 161

Examples

Use cartoons to show Newton's Laws.

Back to Big Ideas Grid I Back to Standard I Back to Index

Curriculum Organizing Questions	What are Newton's Laws? How is this object moving? Which of Newton's Laws describe the movement of this object?
Elaboration	A general exposure to Newton's Laws is all that is expected at this level.
Specific Ideas	Law 1: Every body continues in its state of rest, or of uniform motion in a straight line, unless it is compelled to change that state by forces impressed upon it. Law 2: Force = mass x acceleration. Law 3: To every action force there is an equal and opposite reaction force.
Developmental & Instructional Implications	The force/motion relationship can be developed more fully now and the difficult idea of inertia be given attention. Students have no trouble believing that an object at rest stays that way unless acted on by a force; they see it every day. The difficult notion is that an object in motion will continue to move unabated unless acted on by a force. Telling students to disregard their eyes will not do the trick--the things around them do appear to slow down of their own accord unless constantly pushed or pulled. The more experiences the students can have in seeing the effect of reducing friction, the easier it may be to get them to imagine the friction-equals-zero case. Benchmarks p. 90. The early introduction of the concept of momentum in qualtitative terms prior to considering forcesis an important porposal with considerable support. Although in traditional courses this has been seen as a mathematical motion to be faced by older pupils, many studies nsuggest that we need to offer the idea of momentum so that pupils can attach to it their own idea that a moving object has something which keeps it going. ... There is a general suggestion that Newtonian ideas about motion become harder to accept as pupils become firmer in their own dynamcis. Intorducing momentum before force then allows force to be seen as that which causes a change in momentum, and it prevents the label "force' being attached to the pupils' notion of "something in the object which keeps it moving." Driver p. 161
Examples	Use cartoons to show Newton's Laws.