Dr. SaMeH S. Ahmed

Civil and Environmental Engineering Department

Elliptic orbit2


Elliptic orbit


In astrodynamics or celestial mechanics an elliptic orbit is a Kepler orbit with the eccentricity less than 1; this includes the special case of a circular orbit, with eccentricity equal to zero. In a stricter sense, it is a Kepler orbit with the eccentricity greater than 0 and less than 1 (thus excluding the circular orbit). In a wider sense it is a Kepler orbit with negative energy. This includes the radial elliptic orbit, with eccentricity equal to 1.

In a gravitational two-body problem with negative energy both bodies follow similar elliptic orbits with the same orbital period around their common barycenter. Also the relative position of one body with respect to the other follows an elliptic orbit.

Examples of elliptic orbits include: Hohmann transfer orbitMolniya orbit and tundra orbit.


Velocity

Under standard assumptions the orbital speed (v,) of a body traveling along elliptic orbit can be computed from the Vis-viva equationas:

v=sqrt{muleft({2over{r}}-{1over{a}}
ight)}

where:

The velocity equation for a hyperbolic trajectory has either + {1over{a}}, or it is the same with the convention that in that case a is negative.

[edit]Orbital period

Under standard assumptions the orbital period (P,!) of a body traveling along an elliptic orbit can be computed as:

P=2pisqrt{a^3over{mu}}

where:

Conclusions:

[edit]Energy

Under standard assumptions, specific orbital energy (epsilon,) of elliptic orbit is negative and the orbital energy conservation equation (the Vis-viva equation) for this orbit can take the form:

{v^2over{2}}-{muover{r}}=-{muover{2a}}=epsilon<0

where:

Conclusions:

  • For a given semi-major axis the specific orbital energy is independent of the eccentricity.

Using the virial theorem we find:

  • the time-average of the specific potential energy is equal to 2ε
    • the time-average of r−1 is a−1
  • the time-average of the specific kinetic energy is equal to –ε

[edit]Flight path angle

The flight path angle is the angle between the orbiting body's velocity vector (= the vector tangent to the instantaneous orbit) and the local horizontal. Under standard assumptions the flight path angle phi satisfies the equation:

h, = r, v, cos phi

where:

[edit]Equation of motion

See orbit equation

[edit]Orbital parameters

The state of an orbiting body at any given time is defined by the orbiting body's position and velocity with respect to the central body, which can be represented by the three-dimensional Cartesian coordinates (position of the orbiting body represented by x, y, and z) and the similar Cartesian components of the orbiting body's velocity. This set of six variables, together with time, are called the orbital state vectors. Given the masses of the two bodies they determine the full orbit. The two most general cases with these 6 degrees of freedom are the elliptic and the hyperbolic orbit. Special cases with less degrees of freedom are the circular and parabolic orbit.

Because at least six variables are absolutely required to completely represent an elliptic orbit with this set of parameters, then six variables are required to represent an orbit with any set of parameters. Another set of six parameters that are commonly used are the orbital elements.

The Best Book

Prayer Times

Click here




Office hours

Sunday:      10-1

Monday:      12-1

Wednesday: 10-11

You are welcome to contact me by at any time

You  may also contact me via WhatsApp group

Ext. 2524

Time Table 2018-19S


Civil Eng. Students


DON'T miss!

Love your department and be proud of your field of study

As we approaching the second midterm exams..  Get ready and remember our offices are open to answer you . do not hesitate to .contact me if you have difficulties

For CE 370 students : Your second midterm exam will be on Wednesday 27 March 2019. In the surveying lab

Good Luck


Announcements


My Dear Students

Please visit the  announcement box for the relevant course and make sure that you can download and upload easily, otherwise

.contact me  to sort it out

There will be an orientation session in the midell of this term to help you select your track in Civil and Environmental Engineering

Special Event

Special Issue

Electrical Power Resources: Coal versus Renewable Energy



Published Online on January 2016


Mining Engineering


Mining engineering is an engineering discipline that involves practice, theory, science, technology, and the application of extracting and processing minerals from a naturally occurring environment. Mining engineering also includes processing minerals for additional value.

Environmental Engineering


Environmental engineers are the technical professionals who identify and design solutions for    environmental problems. Environmental engineers provide safe drinking water, treat and properly dispose of wastes, maintain air quality, control water pollution, and remediate sites contaminated due to spills or improper disposal of hazardous substances. They monitor the quality of the air, water, and land. And, they develop new and improved means to protect the environment.

Proverb

Actions speak louder than words

Tawasl


College of Eng. MU

http://mu.edu.sa/ar


Univeristies

Universities I've worked in


Assuit University (Home University), Egypt


Imperial College, London, UK


Faculty of Engineering, Al-Mergeb University, Libya


King Saud University, KSA

,Majmaah University


Majmaah University has a very nice web page that provide  all information regarding deanships, colleges, activities,  campuses and many others. Search your request in
http://mu.edu.sa/en

Also visit

My Academic Pages

https://www.researchgate.net/profile/Sameh_Ahemd

and give me


Think


??

Sports

Ahly vs Zamalek, 30 March 2019

Africa Nation Cup, June 2019


Course 2018/19-2


  1. Surveying 1 CE 370
  2. Surveying II  CE 371
  3. Senior Design II  (round 6) CE 499




The Rules of Life

Rule #1


Latest

Member of the Editorial Board: " Journal of Water Resources and Ocean Sciences"  2013 till now

https://www.researchgate.net/profile/Sameh_Ahmed5/?ev=hdr_xprf

Participating in The Third International Conference on Water, Energy and Environment,(ICWEE) 2019 - American University of Sharjah, UAE 26-28 March 2019 with a Paper and Poster

New article


Coming soon



2nd Midterm Exams on 3/4/2019

Student Conference



Participation  in the 6Th Student Conference

With a paper and oral presentation

From the Senior Design Project CE499 -35

See inside, the paper, and presentation

CE 370 Course

Surveying I

2018-2019S




Power point


Sheets


Lecture notes
15

3-4-2019

:Second Midterm Exam



Results


Model Answer
Inside, please follow

Working  marks is available -Click on Surveying I

CE 371 Course

Surveying II

2018-2019-2




Lectures





First midterm exam


Lab


Results

See Inside

Working marks out of 60 is  available- Click on Surveying 2

CE 474 Course

Photogrammetry

2018-2019-1



Available 0-1-2-3-4 Power point

Available

Quizzes 2 and 3 with model Answer

Quizzes
Available Chapter 1,2,3,4,5 Lecture notes

Report 1  Cameras Report

Y

60 marks Exams

See Inside

Student Performance Records


CE 499 Course

Senior Design 2


Second Best paper from Senior Design Projects in 2015

Paper title:

Evaluation of Groundwater Quality Parameters using Multivariate Statistics- a case Study of Majmaah, KSA

Students:

Abdullah A. Alzeer

Husam K. Almubark

Maijd M. Almotairi

Engineering Practice


A must for Engineer

Useful Links

Google

See what can you get from Google!! more than translation and locations

http://www.googlealert.com/

http://blogsearch.google.com/

http://books.google.com/

http://earth.google.com/

http://finance.google.com/finance


?What is your opinion

Email me in:  [email protected]


Saudi Vision 2030

Sustainability

Learn more about it


Riyadh Metro

A job opportunity 

Safe Fly


Surveying 2-19-3

JEAS

Conversion-Hegira to AD

Conversion


SDL

Saudi Digital Library

Research-gate

Visit me in RG

Success


Contact me

Mobile: 00966598311652

[email protected]

Civil and Environmental Engineering Department
College of Engineering, Majmaah University
Majmaah, P.O. 66, 11952, KSA

Thank you

خالص شكري وتقديري

إحصائية الموقع

عدد الصفحات: 2066

البحوث والمحاضرات: 2042

الزيارات: 69665