Shadowing Practice: Orbital Mechanics - Newton's Laws - Learn English Speaking with Video
בחר מצב תרגול
כל מצב פותח חדר תרגול במסך מלא.
102 משפטים
אם המשפטים קצרים או ארוכים מדי, לחץ על ערוך כדי להתאים אותם.
1
All right, so welcome back.
2
So today's lecture is going to be very short because all we need to cover to finish chapter one are Newton's laws.
3
And the reason why we need to review Newton's laws of motion as well as Newton's gravitational law is
4
because in the previous lecture we looked at kinematics where we saw techniques
5
and methods to study the motion in a force-free environment.
6
But when you think about a spacecraft orbiting a planet, there are obviously external forces being applied to our spacecraft and precisely gravitational forces.
7
So in order to be able to solve the motion, we need to invoke dynamics.
8
And again, the basis to start with dynamics is to review Newton's laws.
9
So first up, we have in 1.5.1, we have Newton's laws. of motion.
10
So there are three laws of motions derived by Newton.
11
The first one is known as the law of inertia.
12
That law says that unless being acted by an external force, a particle in motion will remain in uh in set motion
13
without the mean deviation will remain in a recti linear motion
14
okay uh let me just write it down for you for completeness
15
so this law states that unless acted upon by force
16
A particle will
17
remain in its
18
state of rest or will remain
19
in a straight line, motion with constant
20
inertial velocity.
21
Okay?
22
So all this to say that unless you perturb or push or pull on particle, well that particle will just continue its motion.
23
Okay, that's obvious.
24
And this is the law we observe in my laboratory where we have the granite table upon
25
which are floated spacecraft platform and because of
26
that they aren't experiencing any frictional effects and as such
27
if you were to push a platform in my lab the
28
platform will continue traveling with constant velocity in its initial direction
29
without any deviation thanks to the law of inertia as stated by Newton.
30
Okay so that was the first law of motion discovered by Newton.
31
The second one which is probably his most famous law is is f equal ma
32
okay so in a vector form you just say
33
that the net force being applied to the particle is equal
34
to the mass of the particle times its acceleration in a vector form
35
you could also reformulate that to solve for the acceleration
36
that the particle will experience given the net force being applied
37
to it all right pretty self-explanatory one thing to realize here is
38
that this acceleration you see on the left hand side of that equation acceleration is always the inertial acceleration.
39
Alright, so again, the acceleration in Newton's second law, F equal to mA, is always the inertial acceleration,
40
always, always, always, such that you could say
41
that this is the velocity vector inertial derivative or equivalently double inertial derivative of the position vector r
42
and this is why we studied previously how to relate the inertial acceleration to the non-inertial acceleration
43
because it was such a big deal to obtain the inertial acceleration right by virtue of newton's second line
44
that we're going to reuse ultimately in chapter two to come up with the spacecraft orbital dynamical equation okay
45
so second law of motion by newton finally we're down to the last one so this is the law of action
46
reaction, which says that for every applied force
47
is an equal and opposite reaction force.
48
Okay, so if you have a particle, say M1, and a particle M2 over there,
49
if M1 exerts a force on M2, say it's pulling on m2 like
50
that with f21 well then m2 will also exert the force on m1 of equal magnitude
51
but in opposite direction f12 all this to say that If F21 is the action,
52
you're going to get a reaction in the opposite direction,
53
like that, where F21 is equal to minus F12.
54
okay so same magnitude yet opposite direction what did I just say here that doesn't make any sense
55
f21 is unequal to minus f21 so if if you have f21 like that you get f12 like this
56
And they are in equal magnitude but opposite direction.
57
And that's all I wanted to say.
58
Apologies for that.
59
All right, so these are the three laws, as stated by Newton.
60
But perhaps the most important one in our context here is the law of gravitation.
61
Newton's law of gravitation. and 1.5.2.
62
So, that's considered a case again where we have two masses, M1 and M2.
63
And now we're looking specifically at gravitational forces.
64
So, we have M1 attracting M2 towards itself.
65
with a force being denoted F21 as previously.
66
So we're going to say that F21 vector
67
is the force of attraction on M2 by M1.
68
So M1 attracts M2 essentially.
69
And then you have the opposite direction, F12,
70
or F12 is the force of attraction applied on M1 exerted by M2.
71
and again by virtue of Newton's third law they are equal to magnitude yet in opposite direction
72
now Newton was able to quantify mathematically those gravitational forces
73
or attraction forces by virtue of the fact
74
that those point masses have finite mass of a kilogram
75
and the way they're quantified is F21 is equal to minus capital G where this is known as the universal
76
gravitational constant times m1
77
times m2 times r21 where r21 is the position vector of mass 2
78
with respect to mass 1 I'm just going to move my F12
79
and that makes a lot of sense because if R21 is to the right
80
then you get F, if R21 is to the right, F21 is to the left, like that, in opposite direction.
81
And all this is divided by R21 into the position of M2 with respect to M1.
82
The norm of that, cube.
83
So this is quantifying the gravitational forces of M1 attracting M2 towards it.
84
And similarly, you could solve for F21,
85
or sorry, F12, by saying that this is now a force in the same direction as R21.
86
So this time we don't have the minus in front of everything.
87
So G, M1, M2, R21,
88
position vector, over the distance between those two masses, Q.
89
By the way, this gravitational constant, you don't have to remember
90
that on top of your head in an exam I'm going to provide all constants for you
91
but for completeness this constant is given by 6.6732 times
92
10 to the negative 11 newton meter square over kilogram square.
93
And this concludes Chapter 1.
94
Alright?
95
So in Chapter 2, we're going to start right away by using those gravitational forces,
96
specifically in case of a planet attracting the spacecraft towards itself and thereby creating an orbit around itself.
97
Okay?
98
Hope you enjoyed Chapter 1.
99
Congratulations, you survived.
100
That wasn't an easy chapter to go through was pretty dry
101
a lot of new theory new mathematical operator mathematical objects the vector c's the hollow dot all those great things
102
but you made it thus far congrats and i'll see you again in chapter two soon see you
הורד אפליקציה
כל מה שאתה צריך כדי לדבר בשטף
הגיית AIציון לכל משפט
תרגול IPAשלוט בכל צליל
אוצר מיליםבנה את מאגר המילים שלך
משחק אוצר מיליםלמד תוך כדי משחק
FOR YOU
המלץ על סרטון
C1464 משפטים
Lec 1 | MIT 18.06 Linear Algebra, Spring 2005
TOEFL PrepCambridge Exam PrepUniversity Students
C12
137 משפטים
Newton's Laws: Crash Course Physics #5
Cambridge Exam PrepUniversity Students
B23
133 משפטים
Artemis II Explained | 2026 Mission to the Moon
IELTS PrepTOEFL PrepUniversity Students
C15
148 משפטים
First Law of Thermodynamics, Basic Introduction - Internal Energy, Heat and Work - Chemistry
American AccentIELTS PrepTOEFL PrepCambridge Exam Prep
C18
549 משפטים
Philosophy of Science Lecture #1: Introduction
IELTS PrepTOEFL PrepCambridge Exam Prep
C12
143 משפטים
You Live Inside a Cosmic Hole... And there's a problem
IELTS PrepTOEFL PrepUniversity Students
C13
28 משפטים
Neil deGrasse Tyson: Isaac Newton is #1
IELTS PrepTOEFL PrepUniversity Students
C13
52 משפטים
Human Anatomy Eye
IELTS PrepTOEFL PrepUniversity Students
C13
79 משפטים
The Creation of Chemistry - The Fundamental Laws: Crash Course Chemistry #3
IELTS PrepTOEFL PrepCambridge Exam Prep
C12
124 משפטים
bassham ch3pt1
IELTS PrepTOEFL PrepCambridge Exam Prep
C12
32 משפטים
Equilibrium of Rigid Bodies (2D - Coplanar Forces) | Mechanics Statics | (Solved examples)
Business EnglishUniversity StudentsWorking Adults
C12
400 משפטים
Video
IELTS PrepTOEFL PrepUniversity Students
אוצר מילים והערות הגייה לשיעור הזה
שיעור הדיבור הזה ברמה C1 מבוסס על הסרטון “Orbital Mechanics - Newton's Laws”. המילים שחוזרות הכי הרבה: force, motion, acceleration, particle, equal. בסרטון הזה יש 102 משפטים ו-1174 מילים לתרגול Shadowing. הדיבור נמשך 13:53. הדובר מדבר לאט, כ-85 מילים בדקה, כך שיש זמן לחקות כל צליל. רק 78% מהמילים נמצאות בין 3,000 המילים הנפוצות ביותר באנגלית, כך שאוצר המילים מאתגר.
אוצר מילים מרכזי בסרטון הזה
15 המילים המתקדמות ביותר בסרטון, עם ההגייה והמשמעות שלהן:
| מילה | הגייה | משמעות |
|---|---|---|
| acceleration שם עצם | /əkˌsɛl.əˈɹeɪ.ʃən/ | האצה |
| particle שם עצם | /ˈpɑɹtək(ə)l/ | חֶלְקִיק, גַרגִיר |
| vector שם עצם | /ˈvɛktɚ/ | וקטור |
| spacecraft שם עצם | /ˈspeɪsˌkɹæft/ | חֲלָלִית |
| minus | /ˈmaɪ.nəs/ | פחות, מינוס |
| velocity שם עצם | /vəˈlɑsəti/ | מהירות |
| virtue שם עצם | /ˈvɝt͡ʃu/ | מַעֲלָה, מַעֲלַת טֻכֹּות |
| completeness שם עצם | שלמות | |
| deviation שם עצם | /ˌdiː.viˈeɪʃən/ | סטייה |
| gravitation שם עצם | /ˌɡɹævɪˈteɪ̯ʃən/ | משיכה |
| kilogram שם עצם | /ˈkɪləɡɹæm/ | קִילוֹגְרָם |
| equation שם עצם | /ɪˈkweɪ.ʒən/ | משוואה \ מִשְׁוָאָה |
| orbit שם עצם | /ˈɔɹ.bɪt/ | מַסְלוּל |
| mathematical שם תואר | /ˌmæθ(.ə)ˈmæt.ɪ.kəl/ | מָתֵמָטִי |
| metre שם עצם | /ˈmiːtəɹ/ | מֶטֶר |
הגייה ששווה לשים לב אליה
הדובר משתמש ב-15 קיצורים וצורות מקוצרות, כמו we're, don't, I'm. אמרו אותם בצורה הקצרה, כפי שאתם שומעים אותם.
- הצלילים של “th”: mathematical /ˌmæθ(.ə)ˈmæt.ɪ.kəl/, thereby /ðɛɹˈbaɪ/
- הצלילים של “sh” ו-“zh”: acceleration /əkˌsɛl.əˈɹeɪ.ʃən/, gravitational /ˌɡɹævɪˈteɪʃənəl/, inertial /ɪˈnɜː.ʃəl/, deviation /ˌdiː.viˈeɪʃən/, gravitation /ˌɡɹævɪˈteɪ̯ʃən/
- מילים ארוכות — שימו לב להטעמה: acceleration /əkˌsɛl.əˈɹeɪ.ʃən/, gravitational /ˌɡɹævɪˈteɪʃənəl/, velocity /vəˈlɑsəti/, deviation /ˌdiː.viˈeɪʃən/, gravitation /ˌɡɹævɪˈteɪ̯ʃən/
צלילים שדוברי עברית מתקשים בהם:
- /w/ — שפתיים מעוגלות, לא /v/: quantify /ˈkwɑn.tɪˌfaɪ/, equation /ɪˈkweɪ.ʒən/, unequal /ʌnˈiːkwəl/
- /æ/ — פתוח יותר מה-“אֶ” העברית, לא כמו “a” ב-“cup”: gravitational /ˌɡɹævɪˈteɪʃənəl/, spacecraft /ˈspeɪsˌkɹæft/, magnitude /ˈmæɡnɪtjuːd/, gravitation /ˌɡɹævɪˈteɪ̯ʃən/, kilogram /ˈkɪləɡɹæm/
- /r/ — הלשון לא נוגעת בשום מקום, לא ה-“ר” הגרונית: acceleration /əkˌsɛl.əˈɹeɪ.ʃən/, particle /ˈpɑɹtək(ə)l/, gravitational /ˌɡɹævɪˈteɪʃənəl/, spacecraft /ˈspeɪsˌkɹæft/, gravitation /ˌɡɹævɪˈteɪ̯ʃən/
איך לתרגל עם הסרטון הזה
- הקשיבו לכל הסרטון פעם אחת בלי לדבר, ורשמו את המילים שאתם לא מכירים.
- תרגלו Shadowing משפט אחר משפט במהירות רגילה, וחזרו על כל משפט עד שהקצב שלכם תואם את הדובר.
- הקליטו את עצמכם והשוו למקור, תוך תשומת לב למילים כמו acceleration, particle, vector.
מהי טכניקת השאדואינג?
שאדואינג היא טכניקת למידת שפה מבוססת מדע שפותחה במקור להכשרת מתורגמנים מקצועיים ופופולרית על ידי הפוליגלוט ד"ר אלכסנדר ארגואלס. השיטה פשוטה אך עוצמתית: אתה מקשיב לאודיו באנגלית ילידית וחוזר עליו בקול רם מיד — כמו צל העוקב אחרי הדובר עם עיכוב של 1–2 שניות בלבד. בניגוד להאזנה פסיבית או תרגילי דקדוק, שאדואינג מכריח את המוח והשרירים בפה לעבד ולשחזר דפוסי דיבור אמיתיים בו זמנית. מחקרים מראים שזה משפר משמעותית את דיוק ההגייה, האינטונציה, הקצב, הדיבור המחובר, הבנת השמיעה ושטף הדיבור — מה שהופך אותו לאחת השיטות היעילות ביותר להכנה לIELTS Speaking ולתקשורת באנגלית בעולם האמיתי.