Example 1 Conservation of Momentum Examples If the system includes both the man and the boy it is then an isolated, closed system and momentum is conserved. Man Man / 70. kg Man / 70. kg / 0 m/s Boy Boy / 35 kg Boy / 35 kg / 0 m/s Man Man / 70. kg Man / 70. kg / m/s Boy Boy / 35 kg Boy / 35 kg / ? Initial Final Object / Mass / Velocity + - Momentum + - Object / Mass / Velocity
Example 1 Conservation of Momentum Examples Man Man / 70. kg Man / 70. kg / 0 m/s Boy Boy / 35 kg Boy / 35 kg / 0 m/s Man Man / 70. kg Man / 70. kg / m/s Boy Boy / 35 kg Boy / 35 kg / ? Initial Final Object / Mass / Velocity + - Momentum + - Object / Mass / Velocity Momentum Conservation Equation:
Example 1 Conservation of Momentum Examples Man Man / 70. kg Man / 70. kg / 0 m/s Boy Boy / 35 kg Boy / 35 kg / 0 m/s Man Man / 70. kg Man / 70. kg / m/s Boy Boy / 35 kg Boy / 35 kg / ? Momentum Conservation Equation: Notice the boy has half the mass so twice the velocity! Initial Final Object / Mass / Velocity + - Momentum + - Object / Mass / Velocity
Example 2 a.What is the final velocity of the bullet and the block after the collision? If the system includes both the bullet and the wood it is then an isolated, closed system and momentum is conserved. Bullet Bullet / kg Bullet / kg / 400. m/s Wood Wood / 0.39 kg Wood / 0.39 kg / 0 m/s Combo Combo / 0.40 kg Combo / 0.40 kg / ? Initial Final Object / Mass / Velocity + - Momentum + - Object / Mass / Velocity Conservation of Momentum Examples
Example 2 a.What is the final velocity of the bullet and the block after the collision? Bullet Bullet / kg Bullet / kg / 400. m/s Wood Wood / 0.39 kg Wood / 0.39 kg / 0 m/s Combo Combo / 0.40 kg Combo / 0.40 kg / ? Initial Final Object / Mass / Velocity + - Momentum + - Object / Mass / Velocity Momentum Conservation Equation: Conservation of Momentum Examples
Example 2 a.What is the final velocity of the bullet and the block after the collision? Bullet Bullet / kg Bullet / kg / 400. m/s Wood Wood / 0.39 kg Wood / 0.39 kg / 0 m/s Combo Combo / 0.40 kg Combo / 0.40 kg / ? Initial Final Object / Mass / Velocity + - Momentum + - Object / Mass / Velocity Momentum Conservation Equation: Conservation of Momentum Examples
Example 2 b.What are the initial and final kinetic energies of the bullet, wood block system? This is an inelastic collision. Most of the energy is dissipated and is stored as increased thermal energy in the bullet/block system. Conservation of Momentum Examples