I need help on this as quickly as possible. It is about Newton's Third Law as well as the law of conservation of momentum. I have everything else down but mainly need help with question #3. I believe that the answer for question number three is something on the lines of Newton's Third Law and how forces act in an equal and opposite manner but am not sure. Thanks

Explanation:

In physics, the term conservation refers to something which doesn't change. This means that the variable in an equation which represents a conserved quantity is constant over time. It has the same value both before and after an event.

There are many conserved quantities in physics. They are often remarkably useful for making predictions in what would otherwise be very complicated situations. In mechanics, there are three fundamental quantities which are conserved. These are momentum, energy, and angular momentum. Conservation of momentum is mostly used for describing collisions between objects.

Just as with the other conservation principles, there is a catch: conservation of momentum applies only to an isolated system of objects. In this case an isolated system is one that is not acted on by force external to the system—i.e., there is no external impulse. What this means in the practical example of a collision between two objects is that we need to include both objects and anything else that applies a force to any of the objects for any length of time in the system.

If the subscripts iii and fff denote the initial and final momenta of objects in a system, then the principle of conservation of momentum says

\mathbf{p}_\mathrm{1i} + \mathbf{p}_\mathrm{2i} + \ldots = \mathbf{p}_\mathrm{1f} + \mathbf{p}_\mathrm{2f} + \ldotsp

1i

​

+p

2i

​

+…=p

1f

​

+p

2f

​

+…p, start subscript, 1, i, end subscript, plus, p, start subscript, 2, i, end subscript, plus, dots, equals, p, start subscript, 1, f, end subscript, plus, p, start subscript, 2, f, end subscript, plus, dots

Why is momentum conserved?

Conservation of momentum is actually a direct consequence of Newton's third law.

Consider a collision between two objects, object A and object B. When the two objects collide, there is a force on A due to B—F_\mathrm{AB}F

AB

​

F, start subscript, A, B, end subscript—but because of Newton's third law, there is an equal force in the opposite direction, on B due to A—F_\mathrm{BA}F

BA

​

F, start subscript, B, A, end subscript.

F_\mathrm{AB} = - F_\mathrm{BA}F

AB

​

=−F

BA

​

F, start subscript, A, B, end subscript, equals, minus, F, start subscript, B, A, end subscript

The forces act between the objects when they are in contact. The length of time for which the objects are in contact—t_\mathrm{AB}t

AB

​

t, start subscript, A, B, end subscript and t_\mathrm{BA}t

BA

​