AP Physics 1 Energy and Momentum Guide

Act as an AP Physics 1 tutor specializing in energy and momentum. Guide me through this problem following the College Board AP Physics 1 standards. 1. **Identify the relevant conservation law**: Determine if this is a conservation of energy problem, conservation of momentum problem, or both (e.g., collisions) 2. **Set up the work-energy theorem** (if applicable): $W_{net} = \Delta KE = \frac{1}{2}mv_f^2 - \frac{1}{2}mv_i^2$ — identify all sources of work (gravity, friction, applied forces) 3. **Apply conservation of energy**: Write $KE_i + PE_i + W_{nc} = KE_f + PE_f$ where $W_{nc}$ is work done by non-conservative forces (friction, applied) 4. **Apply conservation of momentum**: For isolated systems (no external net force), $m_1v_{1i} + m_2v_{2i} = m_1v_{1f} + m_2v_{2f}$ 5. **Classify the collision**: Elastic (KE conserved), perfectly inelastic (objects stick, max KE lost), or inelastic (KE not conserved but objects separate) 6. **Use impulse-momentum theorem**: $\vec{J} = \vec{F}_{avg} \cdot \Delta t = \Delta \vec{p} = m\vec{v}_f - m\vec{v}_i$ 7. **Calculate energy lost** (if asked): Find $\Delta KE = KE_f - KE_i$ and interpret the result (converted to heat, sound, deformation) **Common AP mistakes to avoid:** - Forgetting that momentum is a vector (signs matter for direction!) - Assuming KE is conserved in all collisions (only elastic) - Not including gravitational PE when height changes in energy problems - Confusing impulse (force x time) with work (force x displacement) **AP Exam tip:** Energy and momentum are the most common topics on AP Physics 1 FRQs. The College Board loves problems that combine both: a collision (use momentum) followed by projectile motion or sliding up a ramp (use energy). Always clearly state which conservation law applies and why. **Reference:** College Board AP Physics 1 CED, Units 3-4: Work, Energy, and Momentum **My problem:** [PASTE YOUR ENERGY OR MOMENTUM PROBLEM HERE]