3: Why do modern vehicles have airbags, and how do they work with crumple zones? Section 6: Conservation of Momentum 1:Explain the law of conservation of momentum. 2: What happens when two cars of equal mass collide head-on while traveling at the same speed? 3: If a heavier car collides with a lighter car,which car experiences more force? Why?

**3: Why do modern vehicles have airbags, and how do they work with crumple zones?**<br /><br />Modern vehicles have airbags to reduce injuries during a collision. They work in conjunction with crumple zones to minimize the force experienced by occupants.<br /><br />* **Crumple zones:** These are designed sections of a vehicle's structure (usually the front and rear) that deform and collapse in a controlled manner during a crash. This controlled deformation absorbs some of the kinetic energy of the impact, lengthening the duration of the collision. By increasing the time over which the change in momentum occurs, the force experienced by the occupants is reduced.<br /><br />* **Airbags:** Airbags supplement the crumple zones by further cushioning the occupants. When a collision is detected, sensors trigger the rapid inflation of airbags. The airbags provide a softer surface for the occupants to collide with than the hard surfaces of the car's interior (steering wheel, dashboard, etc.). Like crumple zones, airbags increase the time over which the occupant's momentum changes, thereby reducing the force.<br /><br />In essence, crumple zones and airbags work together to lessen the severity of impact forces by extending the duration of the collision and providing a cushioning effect.<br /><br /><br />**Section 6: Conservation of Momentum**<br /><br />**1: Explain the law of conservation of momentum.**<br /><br />The law of conservation of momentum states that in a closed system (one where no external forces are acting), the total momentum of the system remains constant before, during, and after any interaction between objects within the system. In simpler terms, momentum is neither created nor destroyed, only transferred from one object to another. This principle is a direct consequence of Newton's Third Law of Motion (for every action, there is an equal and opposite reaction).<br /><br />**2: What happens when two cars of equal mass collide head-on while traveling at the same speed?**<br /><br />If two cars of equal mass collide head-on while traveling at the same speed, and assuming a perfectly inelastic collision (meaning they stick together after impact), they will come to a complete stop. The momentum of one car cancels out the momentum of the other. The total momentum before the collision is zero (since they have equal and opposite momenta), and the total momentum after the collision is also zero.<br /><br />**3: If a heavier car collides with a lighter car, which car experiences more force? Why?**<br /><br />Both cars experience the *same* magnitude of force. This is a direct consequence of Newton's Third Law of Motion. While the heavier car might experience less *acceleration* due to its greater mass (Force = mass x acceleration), the force exerted *on* the heavier car *by* the lighter car is equal and opposite to the force exerted *on* the lighter car *by* the heavier car. The lighter car, having less mass, will experience a greater change in velocity (acceleration or deceleration).<br />