Newton's Law of Inertia (Rosalyn Montgomery)

Author

Rosalyn Montgomery, Emerson Community Charter Middle School

Principle(s) Illustrated

• Newton's 1st law of Motion (Inertia)

Standards

NGSS Science & engineering standards

Planning and Carrying Out Investigations

• Planning and carrying out investigations to answer questions or test solutions to problems

Scientific Knowledge is Based on Empirical Evidence

• Science knowledge is based upon logical and conceptual connections between evidence and explanations.

NGSS Cross-cutting concept standards

Stability and Change

• Explanations of stability and change in natural or designed systems can be constructed by examining the changes over time and forces at different scales.

NGSS Discipline Core Ideas

MS-PS2.A Forces and Motion

• The motion of an object is determined by the sum of the forces acting on it

Questioning Script

Prior knowledge & experience:

This is used as an engage introduction activity to Newton's laws of motion. I then introduce the law of inertia. Students know that a force is a puss or a pull.

Root question:

Why did the penny fall into the glass when the card flew forward? Why didn't the penny fly with the card?

Target response:

The unbalanced force was applied to the card not the penny. When the car flew, the penny was no longer held up by the card (force interaction between the penny and the card removed) so the penny falls down because there is no force to oppose the force of gravity in that moment. Inertia, a resistance to a change in motion.

Common Misconceptions:

• The penny fell and didn't move because it was too heavy.

• Forces are not acting on a stationary object.

Photographs and Movies

References

The Physics Classroom