I understand that they have two similar but different formula’s that both scale differently with velocity. I also understand that momentum has a direction ie. Vectored, and kinetic energy is directionless. What I can’t wrap my head around is how they are seperate properties with differing values and how it interacts with forces on an object.
For example, when an object collides with a wall, momentum drops to zero, the change in momentum requires the wall to exert force on the object and it involves some work done, and therefore energy. At the same time, the kinetic energy of the object is also released as heat(?)
In: 1
To understand momentum and energy, you need to see these equations:
momentum = force * time
energy = force * distance
They both measure the “pushiness” of an object, but they do it in different measures: one do it in time, another – in space.
* Momentum is time-pushiness: it measures how many “seconds of push” an object have. It is related to stopping time.
* Energy is distance-pushiness: it measures how many “meters of push” an object can do. It is related to stopping distance.
It is also easy to explain, why one depends on **v**, and another on v^(2). When the object goes twice the speed, it takes twice the time to stop it – so its time-pushiness (momentum) scales by 2. But the distance-pushiness (energy) goes by a factor of 4: not only the object moves *twice as long*, it also goes *twice as fast!* So the speed has double effect on the distance.
Latest Answers