Melisa Rollins
English Composition
Mrs. Doran
Narrative Essay
Precious Moments
I had always wanted to experience the natural birth of a baby. Although I have five boys, they were all Cesarean births. I never really felt complete because I never got a chance to experience or see what it was like to deliver a baby naturally; that is, until October 1, 2009, when I was finally able to witness the birth of my little nephew, which made me feel connected as I experienced the tears, emotions, labor, and the delivery, which, in turn, made me feel complete for the first time in many years.

It was five o’clock in the morning, and the phone was continuously ringing in my ears. Angrily, I picked it up and said, “Hello?” “I know it’s early, honey, and I’m sorry for waking you up, but your sister is in labor at the hospital, and she is all by herself.”

“Oh, my God, Mom! I live at least seven hours away from her. I will never make it there before she has the baby; will I?”
“You never know, Melisa, all you can do is try. Besides, I know she will feel much better just knowing that you are on your way to be with her.”
“All right, Mom. I will be on the road within an hour. Please tell her not to panic and that I’m on my way.” I was frantically trying to pack clothes, as well as other personal things I would need for the trip. I could not think straight because all I could think about was getting to my sister before she delivered the baby. Just as I had promised, I was on the road within an hour and I called my mom to let her know.

Each time my phone rang, my heart raced with anticipation, wondering if she had already delivered the baby. Mom told me that my sister, Michelle’s, contractions had slowed down tremendously when she received an epidural for the pain. I was very happy to hear that, although I felt selfish for feeling that way. I was hoping and praying that I would make it there in time to see the birth of her baby.

...I. BACKGROUND
Precious metals and gemstones have been a popular investment vehicle especially in Asian countries and on the part of those who are constantly moving from one country to another. Asians have a special fondness for them because precious metals and gemstones have enabled them to survive hard times most especially when the super power waged their wars on our shores. Another reason for this is the presence of many gold deposits and mines in our country.
PLATINUM Platinum is a grayish white metallic element that is soft, dense, very ductile and malleable with a high tensile strength. It has been used in jewelry, dentistry, Xray equipment, medical and surgical instruments and heating units. Due to its relative inactivity, platinum both as a free metal and alloyed with rhodium, is an almost indispensable material for such devices as magneto contacts, spark plug electrodes, radar parts, bomb sights, and computing devices. In the chemical industries, platinum and its alloys are also essential as catalysts and for other uses. Platinum is much more expensive than gold because of its rarity and extensive usage. Platinum is different from white gold because the latter is gold mixed with nickel, zinc and copper. Upon application of nitrate acid, ...

...Sadie D. Hood Lab 8: Moment of Inertia Partner: Florence Doval Due 16 November 2011 Aims: To use a centripetal force apparatus to calculate the moment of inertia of rotating weights, using theories derived from ideas of energy transfer (Im = MR2 (g/2h)(t2-t02)) and point mass appoximation (m1r12 + m2r22). Set Up
Procedure First we measured the weights of two masses and wingnuts that secure them. Then we placed one of the masses on the very end of a horizontal rod on the centripetal force apparatus, 0.162 m away from the centre of the rod, and the other mass 0.115 m away from the centre of the rod. Then we attached a 0.2 kg mass to the bottom of a string and wound the string around the vertical shaft of the apparatus, so that the bottom of the weight rose to the bottom edge of the tabletop the apparatus was on. We measured the distance from the bottom of the weight to the floor, and then let the weight fall to the floor, and measured the time it took to do so. We repeated this measurement, using the same initial height, four more times. Then we took the masses and the wingnuts off the horizontal rod and let the 0.2 kg mass fall in the same way as before, five times. Then we replaced the masses and the wingnuts, but put them both on the edges of the horizontal rod, and repeated the same falling mass measurements five times. We moved the masses in towards the centre of the rod and continued to repeat the falling mass measurements. We moved the...

...Moment of Inertia
1. Abstract
The goal of this study is to understand the transfer of potential energy to kinetic energy of rotation and kinetic energy of translation. The moment of inertia of the cross arm my group measured with the conservation of energy equation is: 0.01044 kg/m2 (with the mass of 15g), 0.01055 kg/m2 (with the mass of 30g), which is kind of similar to the standard magnitude of the moment of inertia of the cross arm: 0.0095 kg/m2 (Gotten by measuring the radius and the mass of the cross arm and use the definition equation of moment inertia). And we also get the moment of inertia for disk: 0.00604 kg/m2, and the ring: 0.00494 kg/m2.
2. Introduction
For that experiment, we use the conservation of energy equation to find the moment of inertia of the cross arm, and then use the definition equation of the moment of inertia to get the exact magnitude for the cross arm, the disk and the ring.
For the first step, finding the moment of inertia of cross arm, we need the conservation of energy equation for the transferring of the energy from the potential energy to the sum of the kinetic energy for both the mass strikes and the cross arm, like equation 1:
Since the mass is falling with uniform acceleration, its final velocity, v, after having fallen through height h can be found by using equation 2:
And the angular velocity of the...

...[pic] The flywheel of an engine has moment of inertia 2.5 kg•m2 about its rotation axis. What constant torque is required to bring it up to an angular speed of 400 rev/min in 8s, starting from at rest?
[pic] A solid, uniform cylinder with mass 8.25kg and diameter 15cm is spinning at 200 rpm on a thin, frictionless axle that stop the cylinder axis. You design a simple friction brake to stop the cylinder by pressing the brake against the outer rim with a normal force. The coefficient of kinetic friction between the brake and rim is 0.333. What must be the applied normal force to bring the cylinder to rest after it has turned through 5.25 rev?
[pic] A 2.2kg hoop 1.2m in diameter is rolling to the right without slipping on a horizontal floor at a steady 3 rad/s. (a) how fast is its center moving? (b) What is the total kinetic energy of the hip? (c) Find the velocity vector of each of the following points as viewed by a person at rest on the ground: i) the highest point on the hoop; ii) the lowest point on the hoop; iii) the point on the right side of the hoop, midway between the hoop and the bottom. (d) Find the velocity vector for each points in part c, except as viewed by someone moving along with same velocity as the hoop.
[pic] A solid ball is released from res and slides down a hillside that slopes downward at 65° from the horizontal. (a) What minimum value must the coefficient of static friction between the hill and ball surfaces have for no...

...Title: Mass Moment of Inertia
Objective:
To determine mass moment of inertia of a part using experimental method.
Theory:
If a part has been designed and built, its mass moment of inertia can be determined approximately by a simple experiment. This requires that the part be swung about any axis (other than one that passes through its CG) parallel to that about which the moment is sought and its period of pendular oscillation measured. Figure 1 shows a part of connecting rod suspended on a knife-edge pivot at ZZ and rotated through a small angle θ.
Its weight force W acts as its CG has a component W sin θ perpendicular to the radius r from the pivot to the CG.
From rotational form of Newton’s equation:
TZZ=IZZ∝
Substituting equivalent expressions for TZZ and ∝;
-Wsin θr=IZZd2θdt2
Where the negative sign is used because the torque is in the opposite direction to angle a.
For small values of θ, sinθ=θ, approximately, so:
-Wθr=IZZd2θdt2
d2θdt2=-WrIZZθ
Equation above is a second order differential equation with constant coefficients that has the well-known solution:
θ=CsinWrIZZt+DcosWrIZZt
The constants of integration C and D can be found from the initial conditions defined at the instant the part of released and allowed to swing.
At: t=0, θ=θmax, ω=dθdt=0;then:C=0, D=θmax
And:
θ=θmaxcosWrIZZt
Equation above defines the part’s motion as a cosine wave that completes a full cycle of period τ sec when...

...THE MOMENTS OF A RANDOM VARIABLE
Definition: Let X be a rv with the range space Rx and let c be any known constant. Then the kth moment of X about the constant c is defined as
Mk (X) = E[ (X c)k ]. (12)
In the field of statistics only 2 values of c are of interest: c = 0 and c = . Moments about c = 0 are called origin moments and are denoted by k, i.e., k = E(Xk ), where c = 0 has been inserted into equation (12). Moments about the population mean, , are called central moments and are denoted by k, i.e, k = E[ (X )k ], where c = has been inserted into (12).
STATISTICAL INTERPRETATION OF MOMENTS
By definition of the kth origin moment, we have:
k =
(1) Whether X is discrete or continuous, 1 = E(X) = , i.e., the 1st origin moment is simply the population mean (i.e., 1 measures central tendency).
(2) Since the population variance, 2, is the weighted average of
deviations from the mean squared over all elements of Rx, then 2 =
E[(X )2] = 2. Therefore, the 2nd central moment, 2 = 2, is a measure of dispersion (or variation, or spread) of the population. Further, the 2nd central moment can be expressed in terms of origin moments using the binomial expansion of (X )2, as shown below.
2 = E[ (X...

...Laboratory VII: Rotational Dynamics
Problem #1: Moment of Inertia of a Complex System
John Greavu
May 8, 2013
Physics 1301W, Professor: Evan Frodermann, TA: Mark Pepin
Abstract
The moment of inertia of a complex system was determined through two different approaches. A string was tied to and tightly wound around a horizontal disc and then strung over a vertical pulley where the other end was then tied to a hanging weight. Underneath and attached through the center of the disc were a spool and shaft (all supported by a stationary stand). A ring was also centered on top of the disc. The shaft, spool, disc, and ring were free to rotate together. The string was then allowed to unravel around the disc, which also allowed the hanging mass to descend. A video of this was taken, uploaded, and plotted in MotionLab where it was used to construct horizontal position and horizontal velocity vs. time graphs. It was predicted that the moment of inertia of the system was equal to the sum of the individual moment of inertias (for each object in rotation). After analyzing the data and the subsequent graphs, the moment of inertia for the system was also determined as a function of the mass of the hanging weight, the radius of the disc, gravity, and the acceleration of the hanging weight. This function was then compared to the original prediction equation.
Introduction
“While examining the engine of your friend’s snow...

...A Guide to the London Precious Metals Markets
The London Platinum & Palladium Market
Contents
Preface Introduction The London Bullion Market Association The Members Market History The London Platinum and Palladium Market The Members Market History An Over the Counter Market Market Fundamentals What sets London Apart? Market Basics Market Conventions Market Regulation Dealing and Products Users of the London Precious Metals Market Dealing Basics The London Gold and Silver, Platinum and Palladium Fixings Borrowing, Lending and Forward Transactions Precious Metals Loans and Deposits Precious Metals Forwards Options in the Precious Metals Markets Additional Dealing Facilities Deferred Accounts Spot Deferred Forward Contract Inventory Loans Gold Forward Rate Agreements (FRA) and Interest Rate Swaps (IRS) FRA & IRS Credit Risk Exchange for Physical (EFPs) Support Facilities Vaulting Clearing Standard Documentation Taxation Glossary of Terms Bar Weights 28 28 30 30 30 31 33 34 48 15 16 16 21 23 24 24 25 26 1 2 2 2 3 3 3 4 4 6 6 7 11 12 13 13 13 14
Preface
This guide to the London precious metal markets was produced and is published jointly by the London Bullion Market Association (“LBMA”) and the London Platinum and Palladium Market (“LPPM”). It updates the previous guide issued by the LBMA in 2001 (which covered the markets for gold and silver bullion) and extends the coverage to...