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Correction to total final velocity for projectile | Physics | Khan Academy

Video vocabulary

total

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US / ˈtəʊtl /

UK / ˈtoʊtl /

A1
  • adjecitve
  • Complete
  • noun
  • Whole number or amount of something
  • verb
  • To damage a car beyond repair

number

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US / ˈnʌmbə(r) /

UK / ˈnʌmbɚ /

A1
  • noun
  • Symbols such as 1, 2, 56, 793
  • Particular song or dance performed during a show
  • Total quantity or amount of things
  • verb
  • To put numbers on things
  • To assign a sequence within a group, series, set
  • To claim to be part of a larger group, series, set

happen

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US / 'hæpən /

UK / ˈhæpən /

A1
  • verb
  • To take place or occur

arc

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US / ɑ:k /

UK / ɑrk /

B2
  • noun
  • Smoothly curving line or movement
  • verb
  • To bend in a smooth curve

roughly

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US / ˈrʌfli /

UK / ˈrʌflɪ /

B1
  • adverb
  • Approximately; (of numbers) about; around
  • In a manner that is violent or not careful
  • In an inexact, imprecise or violent way
  • In a basic, simple manner

right

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US / raɪt /

UK / raɪt /

A1
  • adjecitve
  • Correct or true
  • The south side of you looking at the rising sun
  • adverb
  • Exactly in a place or time
  • Being appropriate for a particular event
  • In a straight or direct manner
  • noun
  • Something you are legally or morally allowed to do
  • Ideal of what is just and good
  • Political view based on conservatism
  • verb
  • To fix something previously wrong or unjust
  • To make upright, as a boat that has turned over

value

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US / 'vælju: /

UK / ˈvælju /

A1
  • noun
  • Importance you attach to something
  • Some information expressed as a number
  • Stated price of something; worth
  • verb
  • To place a high importance on something
  • To say how much money something is worth

again

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US / ə'ɡen /

UK / əˈɡɛn /

A1
  • adverb
  • One more time, once more

then

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US / ðen /

UK / ðɛn /

A1
  • adverb
  • A time that is not now
  • Following another thing in time or arrangement
  • Following on reasonably from what was just stated
  • At that time, not now

square

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US / skweə(r) /

UK / skwɛr /

A2
  • adjecitve
  • Being fair or honest
  • Multiply a number by itself e.g. 2x2 or 6x6
  • noun
  • Shape with 4 equal length sides and 4 equal angles
  • The result of multiplying Length by the width
  • Open public area in the middle of the town
  • verb
  • To make something balance or be equal
  • To multiply a number by itself, e.g. 2x2 or 6x8
  • To straighten the edge to form a four-sided shape

down

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US / daʊn /

UK / daʊn /

A1
  • adjecitve
  • Being sad, sick, or unhappy
  • Not operating, working, or functioning as expected
  • adverb
  • In a sitting or lying position
  • Towards or on the ground, floor, or bottom
  • Written or copied onto a piece of paper or book
  • noun
  • A period of play in American Football
  • The soft, smooth hairs that cover a bird's body
  • preposition
  • Along something's path, course, or direction
  • Going from a higher position to a lower position
  • verb
  • To eat or drink very quickly and without stopping

second

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US / 'sekənd /

UK / ˈsɛkənd /

A1
  • adjecitve
  • 2nd; the one following first
  • noun
  • Unit of time; one sixtieth of a minute
  • Short period of time that you wait for someone
  • (Do) soon

that

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US / ðæt /

UK / ðæt, ðət /

A1
  • adjecitve
  • The person or thing being talked about
  • Used to identify something both the speakers know
  • adverb
  • Used to reinforce adjectives and adverbs
  • To such a degree
  • conjunction
  • Used to connect a noun clause
  • Used to introduce an adverbial clause
  • Used to introduce a noun clause
  • determiner
  • Used as a noun to refer to something
  • pronoun
  • Referring an object far away
  • Used to refer to the relative pronoun ‘which’

length

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US / leŋθ /

UK / leŋθ /

A2
  • noun
  • Distance from one end of a pool to the other
  • Measurement of distance or of time

take

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US / teɪk /

UK / tek /

A1
  • noun
  • Filming of a single scene for TV or the movies
  • verb
  • To accept something that is offered
  • To use a method of traveling, e.g. a bus or train
  • To use a camera to make (a photo)
  • To pick up something and go away with it
  • To study a subject in school
  • To attempt to pass (an exam)
  • To require a certain amount of time, money, space

both

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US / bəuθ /

UK / boθ /

A1
  • determiner
  • Used to refer to two things at the same time
  • pronoun
  • Used to refer to two things at the same time

figure

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US / ˈfiɡə /

UK / ˈfɪɡjɚ /

A1
  • noun
  • Your body shape
  • Numbers in a calculation
  • Doll-like thing meant to represent a person
  • Picture or diagram giving information in a text
  • Person who is very important or famous
  • Shape of a person seen indistinctly or in outline
  • Amount that is expressed in numbers
  • verb
  • To appear in a game, play or event
  • To calculate how much something will cost
  • To understand after thinking; work out

direction

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US / də'rekʃn /

UK / dɪˈrɛkʃən, daɪ- /

A2
  • noun
  • When someone tells people what to do
  • Describes the way you are going, e.g. North

should

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US / ʃʊd /

UK / ʃʊd /

A1
  • other
  • Used to indicate what is proper or reasonable

plus

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US / plʌs /

UK / plʌs /

A2
  • noun
  • A benefit or advantage
  • preposition
  • In addition; add
  • In addition to; Indicates a number above
  • Having a value greater than zero

actually

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US / ˈæktʃuəli /

UK / ˈæktʃuəli /

A1
  • adverb
  • Used to add new (often different) information

divide

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US / dɪ'vaɪd /

UK / dɪˈvaɪd /

A2
  • verb
  • To split numbers by another number, e.g. 6 / 2 = 3
  • To separate something into equal pieces

component

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US / kəmˈpəʊnənt /

UK / kəmˈponənt /

A2
  • adjecitve
  • Being a part of something
  • noun
  • One of the parts that something is made up of

too

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US / tu: /

UK / tu /

A1
  • adverb
  • In addition, also; with emphasis
  • Say that something is more than you want

somehow

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US / ˈsʌmhaʊ /

UK / ˈsʌmˌhaʊ /

A1
  • adverb
  • In a way that is not known or certain

here

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US / hɪə(r) /

UK / hɪr /

A1
  • adverb
  • In this place; at this location, position or time

realize

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US / 'ri:əlaɪz /

UK / ˈriəˌlaɪz /

A1
  • verb
  • To become aware of or understand mentally

side

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US / saɪd /

UK / saɪd /

A1
  • adjecitve
  • In addition to the central or most important thing
  • Next to, or very close to, the right or left of
  • noun
  • Position or opinion that is opposite to another
  • Right or left part of a person's body
  • Feature of someone's personality
  • Straight edge of an object
  • One of two or more groups fighting each other
  • verb
  • To decide to agree with one point, not the other

radical

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US / ˈrædɪkl /

UK / ˈrædɪkəl,'rædɪkḷ /

B1
  • adjecitve
  • Very new and different from what is traditional
  • Concerning something's most basic part or form
  • noun
  • Person who believes in extreme political change

end

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US / end /

UK / ɛnd /

A1
  • noun
  • The point where a process or activity stops
  • A point that marks the limit of something; finish
  • Goal or desired result
  • The tip, edge or limit of something
  • verb
  • To be the last part of something

problem

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US / ˈprɒbləm /

UK / ˈprɑbləm /

A1
  • adjecitve
  • Causing trouble
  • noun
  • Something difficult to deal with or causes trouble
  • Question to show understanding of a math concept

with

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US / wɪð /

UK / wɪð, wɪθ /

A1
  • preposition
  • As an employee of a certain company
  • Against something or someone
  • By using something as a means
  • Due to; because of
  • Including
  • Possessing as a feature
  • Related to
  • (Of the manner/attitude by which you do something)
  • Used to express that people or things are together

last

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US / lɑ:st /

UK / læst /

A1
  • adjecitve
  • Most recent; the latest
  • The one before
  • adverb
  • Final; with nothing following; after all others
  • Most recent; the latest
  • determiner
  • The one at the end
  • verb
  • To remain or continue for a certain period of time

could

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US / kəd /

UK / kʊd /

A1
  • other
  • Past form of 'can' to mean have ability
  • Used to ask for something politely, or to offer

meter

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US / ˈmi:tə(r) /

UK / ˈmitɚ /

A1
  • noun
  • Unit of length equal to 100 cm or about 39 inches
  • Device for measuring things e.g. gas
  • Device to put money into to rent a parking place
  • Rhythm of a poem
  • verb
  • To measure water, etc. when it has to be paid for

confuse

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US / kənˈfju:z /

UK / kənˈfjuz /

A2
  • verb
  • To make something unclear or hard to understand

negative

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US / 'neɡətɪv /

UK / ˈnɛɡətɪv /

A2
  • adjecitve
  • Being harmful, unwanted or unhelpful
  • In mathematics, being less than zero
  • Focusing on the bad aspects; pessimistic
  • noun
  • The opposite to a positive electrical charge
  • In grammar, containing words such as 'no' or 'not'
  • Reply to a question or statement that means 'no'
  • Image on camera film used to make a photo

have

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US / həv /

UK / hæv /

A1
  • verb
  • To drink, smoke, eat or use something
  • To experience the effects of something
  • To organize an event, or join in an activity
  • To own, possess, or hold something
  • To cause to happen or produce a particular effect

equal

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US / 'i:kwəl /

UK / ˈikwəl /

A1
  • adjecitve
  • Same in shape, size, or number
  • verb
  • To add up or be the same as

not

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US / nɒt /

UK / nɑt /

A1
  • adverb
  • Word indicating the negative
  • (Used to form the negative of verbs)

horizontal

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US / ˌhɒrɪˈzɒntl /

UK / ˌhɔ:rəˈzɑ:ntl /

B1
  • adjecitve
  • Concerning the horizon
  • A level and flat position

copy

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US / ˈkɒpi /

UK / ˈkɑ:pi /

A1
  • noun
  • A counter for items that are the same
  • Fake product pretending to be an original
  • An imitation of an original
  • A duplicate of a paper printed in a photocopier
  • Written text for printing, use in ads, etc.
  • verb
  • To make something look the same as the original
  • To act in the exact same way as someone else
  • To read and then write down what you read

raw

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US / rɔ: /

UK / rɔ /

B1
  • adjecitve
  • Being uncontrolled or strong, as your emotions
  • Being inexperienced
  • Being in a natural or unchanged state
  • (Of skin) being red and sore on the surface
  • (Of foods) uncooked

angle

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US / ˈæŋgl /

UK / ˈæŋɡəl /

B1
  • noun
  • Place where two lines or surfaces meet

final

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US / ˈfaɪnl /

UK / ˈfaɪnəl /

A1
  • adjecitve
  • That will not be changed; permanent
  • Being the last thing in a series
  • noun
  • Last game in a series in a competition

video

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US / 'vɪdɪəʊ /

UK / ˈvɪdiˌo /

A2
  • adjecitve
  • Of a moving film, with sound
  • noun
  • Recording capturing action with sound
  • verb
  • To make a moving film of, with sound

good

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US / ɡʊd /

UK / ɡʊd /

A1
  • adjecitve
  • Proper, appropriate or right
  • (Of an amount) enough; plenty
  • Excellent; high quality
  • Acting well or properly; of moral character
  • In a positive or happy emotional state
  • noun
  • Advantage or benefit

our

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US / 'aʊə(r) /

UK / aʊr /

A1
  • determiner
  • Belonging to us

vector

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US / 'vektə(r) /

UK / ˈvɛktɚ /

B2
  • noun
  • Math a quantity that has both size and direction

but

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US / bət /

UK / bʌt,bət /

A1
  • conjunction
  • Used before you say something different, opposite

become

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US / bɪ'kʌm /

UK / bɪˈkʌm /

A1
  • verb
  • To begin to be; grow to be; develop into
  • To be suitable for a particular job or role

give

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US / ɡɪv /

UK / ɡɪv /

A1
  • noun
  • Degree of flexibility in something, a material
  • verb
  • To hand over or present something to someone
  • To cause someone to have or experience something

can

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US / kæn /

UK / kən,kæn /

A1
  • noun
  • A metal container for storing food
  • other
  • Able to; have the skill to; have the time to
  • verb
  • To have permission to
  • To be possible to do
  • To preserve food by sealing it in a metal container

magnitude

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US / ˈmægnɪtju:d /

UK / ˈmæɡnɪˌtud, -ˌtjud /

B2
  • noun
  • Number representing force of an earthquake
  • Size or importance
  • Number representing the brightness of a star

you

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US / jʊ /

UK / ju /

A1
  • pronoun
  • Person someone is speaking or writing to
  • Person or people in general

opposite

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US / ˈɔpəzit /

UK / ˈɑpəzɪt /

A2
  • adjecitve
  • Being totally different from
  • noun
  • Person, thing that is totally different to another
  • preposition
  • Across from or on the side facing something

make

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US / meɪk /

UK / mek /

A1
  • noun
  • Product made by a particular company; brand
  • verb
  • To arrange or prepare something e.g. dinner
  • To get to (a place) on time
  • To gain the status of (teacher, lawyer, etc.)
  • To create something by putting things together
  • To earn a certain amount of money at a job
  • To cause or force a person to do something
  • To cause something to happen or be formed

the

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US / ðə /

UK / ðə /

A1
  • article
  • Used to refer to something already mentioned
  • Used to show there is only one of something
  • determiner
  • Used to describe all of a family

lead

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US / li:d /

UK / lid /

A1
  • adjecitve
  • Being the main part in movies or plays
  • noun
  • Wire for electricity, computer, etc.; cable
  • Information that could help to solve a crime
  • Main part in a play or movie
  • Heavy, gray metal element
  • Rope used to tie something to stop it escaping
  • Act of being at the front in a race or game
  • verb
  • To show the way or guide others
  • To be at the front of a race or game
  • To travel in front of; go in advance of others

below

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US / bɪ'ləʊ /

UK / bɪˈlo /

A1
  • preposition
  • In a lower position, place, or level

vertical

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US / ˈvɜ:tɪkl /

UK / ˈvɜ:rtɪkl /

B1
  • adjecitve
  • (Of a line, etc.) going up and down; not horizontal

let

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US / let /

UK / lɛt /

A1
  • verb
  • To allow someone to do something
  • Introducing a suggestion to do something together
  • To rent a house, etc. to others

this

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US / ðɪs /

UK / ðɪs /

A1
  • adjecitve
  • Used to indicate something already been discussed
  • Used to indicate something happening around now
  • adverb
  • An indication by a physical motion or gesture
  • A specific amount of
  • determiner
  • Person, thing, or idea near you
  • pronoun
  • Person, thing that has already been discussed

one

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US / wʌn /

UK / wʌn /

A1
  • pronoun
  • You; we; people in general; someone
  • The thing or person previously referred to
  • adjecitve
  • Used to refer to people generally
  • Being a strong example of (something mentioned)
  • number
  • Number 1

inverse

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US / ɪnˈvɜ:s /

UK / ˈɪnˌvə:s /

B2
  • adjecitve
  • Being the opposite of something else
  • noun
  • Thing that is the complete opposite of another

calculator

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US / 'kælkjʊleɪtə(r) /

UK / ˈkælkjəˌletɚ /

B2
  • noun
  • A small electronic device used for calculation

since

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US / sɪns /

UK / sɪns /

A1
  • adverb
  • At a point before the present time
  • conjunction
  • For this reason; because
  • preposition
  • From the time in the past that

redo

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US / ˌri:'du: /

UK / riˈdu /

B1
  • verb
  • To do over again

velocity

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US / və'lɒsətɪ /

UK / vəˈlɑsɪti /

B1
  • noun
  • Speed in a given direction

just

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US / dʒʌst /

UK / dʒʌst /

A1
  • adjecitve
  • Proper or appropriate; as is deserved
  • Doing or being what is right or fair
  • Legally correct; having enough evidence
  • adverb
  • Almost; nearly
  • Exactly at the time of
  • Exactly (the same as, like)

much

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US / mʌtʃ /

UK / mʌtʃ /

A1
  • adjecitve
  • Very; to a high level or degree
  • adverb
  • A lot; large amount; a high degree of
  • Nearly; basically
  • On many occasions; often
  • noun
  • A large amount; a great quantity

per

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US / pə(r) /

UK / pɚ /

A2
  • preposition
  • In the manner directed or suggested
  • For each; during each

under

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US / ˈʌndə(r) /

UK / ˈʌndɚ /

A1
  • adjecitve
  • In the same place as another thing, but lower
  • adverb
  • In a lower quantity or price than expected
  • preposition
  • According to the terms of an agreement or law
  • Managed or controlled by the authority of
  • Being of a lesser quality or amount than expected
  • Influenced or affected by something or someone
  • Less or lower in age, amount, size or number

early

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US / ˈɜ:li /

UK / ˈɜ:rli /

A1
  • adjecitve
  • Happening or appearing before
  • adverb
  • Coming/happening before others in a time sequence
  • Happening sooner than expected

theta

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US / ˈθi:tə /

UK / ˈθetə, ˈθi- /

C1
  • noun
  • 8th letter of the Greek alphabet

out

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US / aʊt /

UK / aʊt /

A1
  • adverb
  • No longer stylish (e.g. fashion)
  • Away from home, business, or the usual place
  • In a direction/movement away from inside or center
  • noun
  • Act when a batter cannot continue playing
  • verb
  • To tell people a secret

something

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US / ˈsʌmθɪŋ /

UK / ˈsʌmθɪŋ /

A1
  • adverb
  • In some degree or measure
  • noun
  • a person or thing of some value or consequence
  • pronoun
  • Thing that is not yet known or named
  • Approximately

over

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US / 'əʊvə(r) /

UK / ˈovɚ /

A1
  • adverb
  • Finished; no longer happening
  • Towards the ground/away from a standing position
  • noun
  • A set of six consecutive balls bowled in cricket
  • other
  • Finished
  • preposition
  • Showing the relation when a thing is above another
  • On or covering something
  • Above or across something
  • More than you need
  • From one side to the other
  • In the direction of; toward

and

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US / ənd /

UK / ənd, ən,ænd /

A1
  • conjunction
  • Used to refer to two or more things
  • Plus; in addition; on top of that
  • Used to introduce an action that follows another

hope

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US / həʊp /

UK / hop /

A1
  • noun
  • When you wish something will happen; what you wish
  • verb
  • To expect and want something to happen

rest

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US / rest /

UK / rɛst /

A1
  • noun
  • Time when one relaxes, sleeps, or is inactive
  • State in which there is a lack of motion
  • Part of something remaining after some was used
  • verb
  • To stop working or avoid activity to recover
  • (Of dead person) to lie in a grave
  • To lean, support or place something against
  • To not be tired because you had enough sleep
  • Subtitles section
  • In the last video, I realized that I made a mistake near the end, but it’s not a good one, because I copied down the wrong number, and then that led to the rest of the problem not having the right values.
  • We figured out that the vertical component of our velocity earlier in the video is negative 26.03 meters per second.
  • But then I somehow, something happened in my brain, and it became negative 29.03.
  • So this is not negative 29.03.
  • This is negative 26.03 meters per second.
  • So the total velocity, we should have 26.03 squared over here.
  • And then if we evaluate that, and I just did it on my calculator, 26.03 squared plus 5.61.
  • Actually, I did it wrong again.
  • So it’s 5.21.
  • Let me redo it.
  • So 26.03 squared plus 5.21 squared under the radical gives us 26.55.
  • So this right over here should be 26.55 meters per second.
  • So that is the magnitude of our final velocity.
  • So that is the magnitude of our total final velocity.
  • And the angle, since this is not 29.03, this is 26.03.
  • We can say that the tangent of this angle theta, tangent of theta, is equal to just the raw side.
  • This is this value right over here.
  • So it is equal to the length of this vector right over here, which is the opposite side, 26.03, over the length of this vector here, which is 5.21.
  • Or we could say, if we take the inverse tangent of both sides of this, that the angle is equal to the inverse tangent, or the arc tangent, of 26.03 over 5.21.
  • And that gives us, we have the inverse tangent of 26.03 divided by 5.21 gives us roughly 78.7 degrees.
  • So the angle here is 78.7 degrees.
  • And it’s below the horizontal.
  • So we can say that the vector, the final velocity vector, has a magnitude of 26.55 meters per second at a direction of 78.7 degrees below the horizontal.
  • So I hope I didn’t confuse you too much with that mistake at the end of that video.