# 0.18 Phy1160: force and motion -- momentum, impulse, and conservation  (Page 2/14)

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## Supplemental material

I recommend that you also study the other lessons in my extensive collection of online programming tutorials. You will find a consolidated index at www.DickBaldwin.com .

## Discussion

This module will describe and discuss some scenarios which, never having been seen, may be hard for a blind student to imagine. Some of those scenarios can be difficult tobelieve even when you can see them.

The behavior of Newton's cradle is somewhat difficult to believe even when you see it in operation. Newton's cradle is a gadget that is often found in novelty shops. Ittypically consists of an open wood or metal frame with about five steel balls suspended by strings on parallel beams that run from one end to the other alongthe top.

Several steel balls in a row

Each ball is suspended by two strings so that the ball forms the lower vertex of a triangle and the two equal-length strings form the sides of the triangle.Each string is attached at the upper end to a beam. The purpose of suspending each ball by two strings instead of suspending them on a single string is to cause all of the ballsto swing back and forth along the same straight line.

A collision

When the system is in equilibrium, the balls are lined up in a row and each ball barely touches the one next to it. If you pull one of the balls at the endback and then release it, allowing it to swing down, it will strike its neighbor on the downswing.

Only the ball on the other end appears to move

Surprisingly, the neighboring ball doesn't appear to move when struck, nor does its neighbor, nor does that neighbor's neighbor. The only ball that appears to move isthe ball at the far end of the line. That ball will be sent off in an upswing.

The process is reversed

When that ball reaches the top of its upswing, it will reverse direction, swing back down, and collide with its neighbor. This causes the ball that wasused to start the process to be sent off in an upswing.

The process continues

Left alone, this process will continue until all of the energy in the systemhas been dissipated, which can be many minutes or even hours later.

Newton's cradle illustrates the conservation of momentum. You will find an interestingarticle that explains some of the technical details at (External Link)

## Momentum

You learned in an earlier module that momentum is the product of the mass of an object and the velocity of the object. Because velocity is a vector quantity,momentum is also a vector quantity. The direction of the momentum vector is the same as the direction of the underlying velocity vector.

A common symbol for momentum is p

A common symbol for momentum is p . Momentum is a derived item in the SI system of units. In the SI system, momentum is defined as kg*m/s.

In equation form , therefore:

• momentum = mass * velocity, or
• p = m * v in units of kg*m/s

Facts worth remembering -- Momentum

• momentum = mass * velocity, or
• p = m * v

The units of momentum are kg*m/s

Mass in action

Momentum can also be thought of as "mass in motion." Since all objects have mass, if an object is moving, its mass is in motion. Therefore, the object has momentum.

anyone know any internet site where one can find nanotechnology papers?
research.net
kanaga
Introduction about quantum dots in nanotechnology
what does nano mean?
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
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
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
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.
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