Linear Momentum Center of Mass Introduction q Collisions

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Linear Momentum & Center of Mass

Linear Momentum & Center of Mass

Introduction q Collisions q Impulse n n and Linear Momentum Single Collision Series of

Introduction q Collisions q Impulse n n and Linear Momentum Single Collision Series of Collisions q Momentum and Kinetic Energy q Inelastic Collisions in One Dimension n n One-Dimensional Collision Completely Inelastic Collision q Elastic Collisions in One Dimension q Collisions in Two Dimensions

Center of Mass for a System of Particles The center of mass of a

Center of Mass for a System of Particles The center of mass of a body or a system of bodies moves as though all of the mass were concentrated there and all external forces were applied there. 2 bodies, 1 dimension n bodies, 3 dimensions, vector equation

Center of Mass for a Solid Body Differential mass element dm Uniform density

Center of Mass for a Solid Body Differential mass element dm Uniform density

Newton’s 2 nd Law for a System of Particles System of particles A firework

Newton’s 2 nd Law for a System of Particles System of particles A firework rocket explodes A grand jeté

Linear Momentum Particle System Conservation of Linear Momentum If no net external force acts

Linear Momentum Particle System Conservation of Linear Momentum If no net external force acts on a system of particles, the total linear momentum P of the system cannot change. If the component of the net external force on a closed system is zero along an axis, then the component of the linear momentum along that axis cannot change.

Impulse and Linear Momentum Definition of Impulse Collision of two particle-like bodies Impulse–Linear Momentum

Impulse and Linear Momentum Definition of Impulse Collision of two particle-like bodies Impulse–Linear Momentum Theorem Steady stream of projectiles

Momentum and Kinetic Energy q Closed system (no mass enters or leaves) q Isolated

Momentum and Kinetic Energy q Closed system (no mass enters or leaves) q Isolated system (no external net force) q Elastic collision (kinetic energy conserved) q Inelastic collision (kinetic energy not conserved) q Completely inelastic collision (bodies always stick together) In a closed, isolated system containing a collision, the linear momentum of each colliding body may change but the total momentum of the system cannot change, whether the collision is elastic or inelastic.

Inelastic Collisions in 1 D Conservation of Linear Momentum Completely Inelastic Collision Velocity of

Inelastic Collisions in 1 D Conservation of Linear Momentum Completely Inelastic Collision Velocity of Center of Mass

Elastic Collisions in 1 D In an elastic collision, the kinetic energy of each

Elastic Collisions in 1 D In an elastic collision, the kinetic energy of each colliding body may change, but the total kinetic energy of the system does not change. Stationary Target Moving Target