# 0.18 Phy1160: force and motion -- momentum, impulse, and conservation  (Page 6/14)

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A rebound collision

A rebound collision involves a change in direction in addition to a change in speed. Because the direction changes, there is a large velocity change even ifthe magnitude of the velocity stays the same.

Elastic collision

Collisions in which objects rebound with the same speed (and thus, the same momentum and kinetic energy) as they had prior to the collision are known as elastic collisions .

Stated differently, an elastic collision is a collision between two bodies in which the total kinetic energy of the two bodies after the collision is equal totheir total kinetic energy before the collision. Elastic collisions occur only if there is no net conversion of kinetic energy into other forms.

Facts worth remembering -- Elastic collision

An elastic collision is a collision between two bodies in which the total kinetic energy of the two bodies after the collision isequal to their total kinetic energy before the collision.

Energy conversion

A future module will explain kinetic energy and other forms of energy, such as potential energy in detail. Briefly, kinetic energy is energy possessed by amoving object simply because it is moving. For example, it hurts more to be hit by a fast moving baseball than to be hit by a slow moving baseball, simplybecause the collision with a fast moving baseball imparts more energy into your body. In other words, the kinetic energy possessed by the fast-moving baseballis converted into pain in your body.

Characteristics of an elastic collision

An elastic collision is typically characterized by a large velocity change, a large momentum change, a large impulse, and a large force.

While the case of a Super Ball bouncing on a solid concrete floor isn't a perfect elastic collision, it comes very close. The amount of kinetic energythat is converted into other forms of energy during each bounce is very low, and the ball will continue bouncing for a very long time with the height of eachbounce being almost as high as the height of the previous bounce.

## Action and reaction

Two objects collide when they make contact while one or both are moving. As is the case with all interactions involving two or more moving objects, a collisionresults in a force being applied to all of the objects involved in the collision. The behavior of such collisions is governed by Newton's laws ofmotion.

Newton's third law

One paraphrased version of Newton's third law (see (External Link) ) reads:

... in every interaction, there is a pair of forces acting on the two interacting objects. The size of the force on the first object equals the sizeof the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forcesalways come in pairs - equal and opposite action-reaction force pairs.

According to Newton's third law, when two objects are involved in a collision, the two objects experience forces that are equal in magnitude andopposite in direction.

In most cases, the collision will cause one object to gain momentum and the other object to lose momentum. This, in turn, will cause one object to speed upand the other object to slow down.

do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
it is a goid question and i want to know the answer as well
Maciej
Abigail
Do somebody tell me a best nano engineering book for beginners?
what is fullerene does it is used to make bukky balls
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
so some one know about replacing silicon atom with phosphorous in semiconductors device?
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
for screen printed electrodes ?
SUYASH
What is lattice structure?
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
what's the easiest and fastest way to the synthesize AgNP?
China
Cied
types of nano material
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
what is nano technology
what is system testing?
preparation of nanomaterial
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
what is system testing
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
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