### THE PHYSICS CLASSROOM 2009 MOMENTUM PROBLEM SOLVING ANSWER KEY

Both the Volkswagon and the large truck encounter the same force, the same impulse, and the same momentum change for reasons discussed in this lesson. While the two vehicles experience the same force, the acceleration is greatest for the Volkswagon due to its smaller mass. A Tomahawk cruise missile is launched from the barrel of a mobile missile launcher. Observe in the table above that the known information about the mass and velocity of the two objects was used to determine the before-collision momenta of the individual objects and the total momentum of the system. As an equation, this can be stated as. In most collisions between two objects, one object slows down and loses momentum while the other object speeds up and gains momentum.

The following equation results:. For collisions occurring in an isolated system , there are no exceptions to this law. This would produce the effect of “the rifle actually being the bullet. If object 1 contacts object 2 for 0. Useful means of representing such analyses include a momentum table and a vector diagram.

## Momentum Conservation Principle

The two collisions above are examples of inelastic collisions. We Would Like to Suggest However, be certain that you don’t come to believe that physics is merely an applied mathematics course that is devoid of concepts.

The table shows classorom amount of money possessed by the two individuals before and after the interaction. In a collision, eolving momentum change of object 1 is equal to and opposite of the momentum change of object 2.

Read Watch Interact Physics Tutorial. If it can be assumed that the effect of friction between the person and the ice is negligible, then the collision has occurred in an isolated system. Ben disagrees entirely, arguing that that both bug and bus encounter the same force, momentum change, and impulse.

As predicted, the truck has lost momentum slowed down and the car has gained momentum. That is, the momentum lost by object 1 is equal to the momentum gained by object 2. While this is not technically an elastic collision, it is more elastic than the previous collisions in which the two objects stick together.

Consider a collision between two objects – object 1 and object 2. Technically, an inelastic collision is a collision in which the kinetic energy of the system of objects is not conserved. And that’s exactly what you do when you use one of The Physics Classroom’s Interactives.

The next section of this lesson involves examples of problems that provide a real test of your conceptual understanding of momentum conservation in collisions.

To determine v the velocity of both the objects after the collisionthe sum of the individual momentum of the two objects can be set equal to the total system momentum.

The collision causes the ball to lose momentum and the person to gain momentum.

## Using Equations as a Recipe for Algebraic Problem-Solving

Miles and Ben begin discussing the physics of hpysics situation. Label the magnitude of each momentum vector. These Interactives can be found in the Physics Interactive section of our website and provide an interactive experience in analyzing the momentum of individual objects and systems of objects in collisions.

The subject of energy will be treated in a later unit of The Physics Classroom.

# Momentum Conservation Principle

However, physics is about concepts and the variety of means in which they are represented. You have classroon interact with it! Take the time to understand the concept of momentum conservation that provides the basis of their solution. The actual momentum of the loaded cart can be determined using the velocity often determined by a ticker tape analysis and the mass.

Finally, the expression 0. This law becomes a powerful tool in physics because it allows for predictions of the before- and after-collision velocities or mass of an object. The law of momentum conservation will be combined with the use of a “momentum table” and some algebra skills to solve problems pyysics collisions occurring in isolated systems.

If you find this hard to believe, then be sure to read the next question and its accompanying explanation. After the collision, the momenta of the two separate objects dropped brick and loaded cart can be determined from their measured mass and their velocity often found from a ticker tape analysis.

Who do you agree with? Jomentum also shows the total amount of money before and after the interaction.

To simplify matters, we will consider any collisions in which the two colliding thw stick together and move with the same post-collision speed to be an extreme example of an inelastic collision. If object 1 loses 75 units of momentum, then object 2 gains 75 units of momentum. What Can Teachers Do