This is an interactive homework problem for introductory physics students involving conservation of energy and conservation of momentum.  A bullet is fired, embedding itself in a resting pendulum suspended vertically by massless strings.  Given mass of the bullet and pendulum, plus initial velocity of the bullet, how high will the pendulum rise after the collision?  

A user-activated "help" sequence is provided to guide students through each phase of this two-step problem, from conceptual analysis through quantitative calculation.  To promote critical thinking, immediate feedback is received for both correct and incorrect responses.  This item is part of a larger collection of interactive homework problems for introductory physics.  See Related items on this page for a link to the full index of the author's materials.