Energy and Momentum Systems · Weeks 10-18

Conservation of Momentum: Two-Dimensional Collisions

Students will extend the principle of conservation of momentum to analyze two-dimensional collisions.

About This Topic

This topic explores the constitutional 'tug-of-war' over foreign policy and the power to wage war. Students examine the tension between the President's role as Commander-in-Chief and Congress's exclusive power to declare war. They analyze the War Powers Resolution of 1973 and how it attempted (and often failed) to reassert Congressional authority after the Vietnam War.

For 12th graders, this is a lesson in the 'gray areas' of the Constitution. It covers how modern warfare, including drone strikes and cyber attacks, challenges 18th-century definitions of conflict. This topic comes alive when students can physically model the patterns of crisis response and the legal justifications used by both branches to claim authority over national security.

Active Learning Ideas

Formal Debate: The War Powers Act

Students debate whether the War Powers Resolution is a constitutional check on the President or an unconstitutional infringement on the Commander-in-Chief's power. They must use historical examples like the Gulf War or Libya.

⏱ 50 min·Small Groups

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Role Play: Treaty vs. Executive Agreement

Students act as State Department officials. They are given a policy goal (e.g., a climate pact) and must decide whether to pursue a formal Treaty (requires 2/3 Senate) or an Executive Agreement (faster, but less permanent).

⏱ 30 min·Pairs

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Inquiry Circle: The 'Authorization' Search

Students research the 'AUMF' (Authorization for Use of Military Force) passed after 9/11. They investigate how this single act of Congress has been used by multiple Presidents to justify military actions in dozens of countries.

⏱ 45 min·Small Groups

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Watch Out for These Misconceptions

Common Misconception

The US has declared war in every major conflict (like Korea or Vietnam).

What to Teach Instead

The US has only formally declared war five times in its history. Most conflicts are 'authorized' or funded by Congress without a formal declaration. Peer-led 'Conflict Timelines' help students see the shift toward executive-led military action.

Common Misconception

The President can do whatever they want in foreign policy.

What to Teach Instead

Congress still holds the 'Power of the Purse.' If Congress refuses to fund a military operation, the President cannot sustain it. A 'Budget Simulation' helps students see that money is the ultimate check on war-making.

Frequently Asked Questions

What is the 60-day rule in the War Powers Resolution?

It requires the President to withdraw troops within 60 days unless Congress declares war or grants an extension. However, many Presidents have argued this is unconstitutional and have largely ignored the deadline.

How do 'Executive Agreements' differ from 'Treaties'?

Treaties are formal agreements that require Senate approval and become part of US law. Executive agreements are made between the President and a foreign leader; they don't need Senate approval but can be easily undone by the next President.

What are the best hands-on strategies for teaching foreign policy powers?

A 'National Security Council' simulation is the gold standard. By giving students a ticking-clock scenario, they realize that the speed of modern threats often favors executive action over slow congressional deliberation. This surfaces the core tension: do we prioritize constitutional process or national safety?

What is the 'Power of the Purse' in war?

While the President commands the troops, only Congress can pay for them. By threatening to cut off funding for a specific mission, Congress can effectively force a President to end a military engagement without ever passing a law.

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