The volume of any rectangular solid, including a cube, is calculated mathematically as V = l × w × h
How to find a cross-sectional area?In a given calculation, if you are given the:
Length WidthHeightTo find this, you would have to use the area of its base which is:
Length * Width * Height.
Furthermore, if the cross-section is parallel, then you would have to solve it thus:
Length * Width which is the area of the section from top to bottom.
Although your question is incomplete, the general idea of how to find the cross-sectional area of the volume of any rectangular solid.
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An astronomer discovers a new star and wants to measure its temperature. She would typically do this by:____.
An astronomer that discovers a new star and wants to measure its temperature would typically do this by means of a blackbody curve to find the maximum wavelength.
What is the maximum wavelength peak?The maximum wavelength peak is the portion of the wave where a given chemical substance/object exhibits its maximum strongest value of photon absorption.
On the other hand, the blackbody curve of an object is the graphical diagram that shows the distribution of the radiation emitted by this particular substance.
In conclusion, An astronomer that discovers a new star and wants to measure its temperature would typically do this by means of a blackbody curve to find the maximum wavelength.
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A 1-kg book is at rest on a desk. Determine the force the desk exerts on the book
[tex]\displaystyle F_n = 9.8 \ N[/tex]
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to RightPhysics
Forces
SI Unit: Newtons N
Free Body Diagrams
Gravitational Force: [tex]\displaystyle F_g = mg[/tex]
m is mass (in kg)g is Earth's gravity (9.8 m/s²)Normal Force: [tex]\displaystyle F_n[/tex]
Newton's Law of Motions
Newton's 1st Law of Motion: An object at rest remains at rest and an object in motion stays in motionNewton's 2nd Law of Motion: F = ma (Force is equal to [constant] mass times acceleration)Newton's 3rd Law of Motion: For every action, there is an equal and opposite reactionExplanation:Step 1: Define
1 kg book at rest
Step 2: FBD
See Attachment
Draw a free body diagram to label the forces acting upon the book. We see that we would have gravitational force from Earth pointing downwards and normal force from the surface of the desk pointing upwards.
Since the book is not moving, we know that ∑F = 0 (sum of forces equal to 0).
Step 4: Find Normal Force
Define Forces [Newton's Law of Motions]: [tex]\displaystyle \sum F = 0[/tex][Newton's Law of Motions] Substitute in forces: [tex]\displaystyle F_g - F_n = 0[/tex][Newton's Law of Motions] [Addition Property of Equality] Isolate [tex]\displaystyle F_n[/tex]: [tex]\displaystyle F_g = F_n[/tex][Newton's Law of Motions] Substitute in [tex]\displaystyle F_g[/tex]: [tex]\displaystyle mg = F_n[/tex][Newton's Law of Motions] Rewrite: [tex]\displaystyle F_n = mg[/tex][Newton's Law of Motions] Substitute in variables: [tex]\displaystyle F_n = (1 \ kg)(9.8 \ \frac{m}{s^2})[/tex][Newton's Law of Motions] Multiply: [tex]\displaystyle F_n = 9.8 \ N[/tex]How many excess electrons must be distributed uniformly within the volume of an isolated plastic sphere 26.0 cm in diameter to produce an electric field of 1440 N/C just outside the surface of the sphere
a metaphor for generosity and joy and joy and joy and joy organised a large wedding guests had to choose their meal from beef chicken tikka and a kind young women in the streets of St
The number of excess electrons needed to be distributed uniformly in the sphere to produce the given electric field is 1.69*10^(10).
What is an electric field?
The electric force exerted on a unit charge is called the electric field.
For a sphere of uniform charge density, the magnitude of the electric field on its surface is given by,
E=k*q/r^2
where E is the magnitude of the electric field, k is the coulomb's constant which has a value of 9*10^9 N m^(2) C^(-2), and q is the total charge of the sphere, and r is the radius of the sphere.
The radius of the sphere is half of the diameter. Given the diameter of the sphere is 26.0 m, the radius of the sphere r=26.0/2 cm or r=13.0 cm.
It is given that E=1440 N/C, r=13.0 cm, and the value of k is 9*10^9 N m^(2) C^(-2). Substitute these values in the formula of the electric field and solve it to get the value of the total charge on the sphere.
Note: 1 cm = 0.01 m.
1440 (N/C)= (9*10^9 N m^(2) C^(-2))*q/( 13 cm)^2
1440 (N/C)= (9*10^9 N m^(2) C^(-2))*q/( 13*0.01 m)^2
1440 ( N/C)= (532.54*10^(9) N C^(-2))*q
q=1440/(532.54*10^(9)) C
q=2.704*10^(-9) C
Since the charge is quantized, the total charge inside the sphere is the integral multiple of an elementary charge. In the given case, the value of that elementary charge is 1.6*10^(-19) C. The total charge is then given by,
q=ne
where q is the total charge, n is the number of elementary charges and e is the value of the elementary charge.
The value of q is 2.704*10^(-9) C and the value of e is 1.6*10^(-19) C.
Substitute these values in the formula of total charge and solve it to get the number of elementary charges.
2.704*10^(-9) C =n*1.6*10^(-19) C
n=2.704*10^(-9)/ 1.6*10^(-19)
n=1.69*10^(10)
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Is it resistant to mud fire
Dirt that you can not burn typically does no longer have any materials that are flammable at decrease temperatures. Mostly due to the fact it is full of water and non-burnable minerals. But a lot of what's in grime can certainly burn if it is dried. Dirt is made of many unique things.
yes
Explanation:
since they are extremely dense they lack the ability to trap air due to its structure
Mr. Rosa is able to travel at 10m/s. How much time will it take him to travel a distance of 542 meters?
What is the known?
What is the unknown?
Plug it in.
What is your answer?
// s - displacement, t - time, v - velocity
Known:
s = 542 meters;
v = 10m/s
Unknown:
t - ?
Formula:
t = s / v
Solution:
t = 542 / 10 = 54,2 (s)
Answer:
54,2 s
Make me the brainliest, please
Medical applications of ultrasound use frequencies up to 2.00 × 10^7 hz. What is the wavelength of this frequency in 20 °c air?
The wavelength of the ultrasound wave in 20 °c air is 1.715 * 10⁻⁵ m.
What is the relationship between wavelength and frequency of a wave?The frequency of sound is the number of complete oscillations per second.
The wavelength is the distance between successive positions in the wave.
Velocity of sound is the distance covered per second.
The frequency and wavelength of a wave are related by the formula given below:
Velocity = frequency * wavelengthThe velocity of sound in 20°C air = 343 m/s
frequency of the sound wave = 2.00 × 10⁷ hz or 2.00 × 10⁷ s⁻¹
wavelength = velocity/frequency
wavelength = 343 / 2.00 × 10⁷
wavelength = 1.715 * 10⁻⁵ m
In conclusion, the wavelength of the ultrasound wave is determined from the ratio of the velocity and the frequency of the sound.
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the unit of acceleration is derived unit why
Answer:
Mass is a base unit, acceleration is a derived unit calculated as a function of length and time which are both base units. Any unit definition that is a function of more basic units is considered a derived unit.
how was youll day still in school by the way.
My day is alright! I just finished school for the day.. and I’m excited for the weekend! How was your day?
What is the only part in our body we do not stretch?
Answer:
The quadriceps consists of four muscles: the skinny rectus femoris and the three huge “vasti” — vastus lateralis/intermedius/medialis. The vasti are only elongated by knee flexion, which is limited to about 120˚ when the calf hits the hamstrings. The vasti cannot be stretched strongly.
Answer:Masseter and temporalis
Why it’s unstretchable: The jaw can only open so far.
Why it’s a dang shame: Jaw tension is epidemic, and trigger points in these muscles cause a wide array of strange face and head pains, including toothaches, headaches, and earaches.
A 1436. 32' line has an azimuth of 178 52 13. What is the latitiude and departure of the line?
Latitude of the line will be = 1436.033
Departure of the line will be = 28.152
Given
let line be = a = 1436. 32
azimuthal be = x = 178° 52' 13''
This line must have two components , one is horizontal component which is its latitude and other will be vertical component which is departure . Resolving both the components we get,
latitude = a*cos(178° 52' 13'')
= 1436. 32 * cos(178° 52' 13'')
= 1436. 32 * (- 0.9998)
latitude = 1436.033
departure = a * sin (178° 52' 13'')
= 1436. 32 * 0.0197
departure = 28.152
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What are true statements that reflect why infants experience more fluid and electrolyte changes?
True statements that reflect why infants experience more fluid and electrolyte changes are that dehydration can upset the balance of electrolytes in an infant or child and the newborn is at risk of excessive water loss and hypernatremia as the result of high evaporative water loss through the skin.
As infants are not used to the environment around , they are more sensible towards problems such as Dehydration because of fast metabolism.
Dehydration can upset the balance of electrolytes in an infant or child. Children are especially vulnerable to dehydration due to their small size and fast metabolism, which causes them to replace water and electrolytes at a faster rate than adults.
Infants are particularly prone to the effects of dehydration because of their greater baseline fluid requirements (due to a higher metabolic rate), higher evaporative losses (due to a higher ratio of surface area to volume), and inability to communicate thirst or seek fluid.
The newborn is at risk of excessive water loss and hypernatremia as the result of high evaporative water loss through the skin, insensible water loss (IWL), as well as decreased capacity to concentrate the urine.
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A 0.10-m 3 0.20-m 3 0.30-m block is suspended from a wire and is completely under water. What buoyant force acts on the block
The buoyant force acting on the block is 58.8 N.
Calculation:The dimensions of the block are given as 0.10 m, 0.20 m and 0.30 m.
The volume of the block will be = 0.10 × 0.20 × 0.30 m³
= 0.006 m³
We know that,
W = mg .....(1)
where,
W = weight of the block
m = mass of the block
g = acceleration due to gravity = 9.8 m/s²
We also know that mass is proportional to density and volume
m = ρ.V .....(2)
Substituting the equation (2) in (1)
W = ρ.V.g .....(3)
Density of water, ρ = 1000 kg/m³
Force is the net weight acting on the block
F = W = ρ.V.g
F = 1000 × 0.006 × 9.8
F = 58.8 N
Therefore, the buoyant force acting on the block is 58.8 N.
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The following figures show four positions (1-4) of a comet during its orbit of the Sun. Also shown is the orbit of the Earth around the Sun. Rank the positions of the comet from left to right based on the size of its tail, from shortest to longest. (Not to scale; tails not shown.)
3, 1, 2, 4 is the arrangement according to their comet's tail.
The length of a comet's tail depends primarily on the comet's distance from the sun. It is longer when the comet is closer to the sun and shorter or (Negligible) when the comet is farther from the sun.
Due to sunlight's radiation pressure, the comet's tail will always point away from the sun. Small dust particles are pushed away from the sun by sunlight with a stronger force than by gravity pulling them in the opposite direction. As a result, a comet's tail streams behind the nucleus during its inbound transit, but it streams in front of the nucleus during its outbound passage back to the outer solar system. Typically, gas jets produced by thawing frozen volatiles expel dust particles from a comet's surface.
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In the absence of a strong magnetic field), what is the chief factor that determines what type of electromagnetic radiation objects give off:____.
The chief factor that determines what type of electromagnetic radiation that objects give off in the absence of a strong magnetic field is their temperature.
What is the radioactive activity?The radioactive activity refers to the energy that a atomic nucleus can release in a given period of time due to the emission of different types of radiation.
This activity (radioactive activity) increases as temperature rises due to a higher collision of subatomic particles that form molecules.
In conclusion, the chief factor that determines what type of electromagnetic radiation in the absence of a magnetic field is temperature.
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The center of gravity of the body is at________ position in state of unstable equilibrium.
Answer:
Highest.
Explanation:
This is because, in a state of unstable equilibrium, the center of gravity is at highest which as a result of when the body topples at it's base, there is a shift in the centre of gravity, and the centre of gravity shift position by moving towards the lower position and it does not return to it's former position again.
An electron moving through an electric field is observed to have an acceleration of 1.20 1016 m/s2 in the x direction. What is the magnitude and the direction of the electric field that produces this acceleration
The magnitude is 5.69 × 10^4 N/C and the direction is opposite to the acceleration of electron.
Equation of force on a charge is -
F = ma
→ qE = ma
The acceleration of an electron is 1.201016 m/s².
→ E = ma/q
plug in the values
E = 9.11 × 10^-31 kg × 1×10^16 m/s² i / -1.6 × 10^-19 C
E = 5.69 × 10^4 N/C (-i)
so, magnitude is 5.69 × 10^4 N/C and field is along negative x-axis
Thus, it has opposite direction to the acceleration of electron.
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(10%) Problem 2: The frequency range for AM radio is 540 to 1600 kHz. The frequency range for FM radio is 88.0 to 108 MHz.
188m - 556m is the wavelength range for AM radio.
2.77 - 3.40m is the wavelength range for FM radio.
1) For AM radio
f(max) = 1600 × 10³ Hz
f(min) = 540 ×10³Hz
c = fλ
λ = c/f where,
c = speed of light
f = frequency
λ= wavelength
So,
λ(min) = 3 × [tex]10^{8}[/tex] / 1600 × 10³ = 188 m
λ(max) = 3 × 10⁸/540 ×10³ = 556 m
So wavelength range of AM radio is 188 m - 556m
2) For FM radio
f(max) = 108 × 10⁶ Hz
f(min) = 88 × 10⁶ Hz
λ(min) = 3 × 10⁸ / 108 × 10⁶ = 2.77 m
λ(max) = 3 × 10⁸ / 88 × 10⁶ = 3.40 m
So wavelength range of FM radio is 2.77m - 3.40m
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A box of mass 8 kg slides across a frictionless surface at an initial speed 1.5 m/s into a relaxed spring of spring constant 69 N/m.
Time for which box will remain in contact with spring is 1.1 sec
Given:
mass of box = 8 kg
initial speed of box = 1.5 m/s
spring constant = 69 N/m
To Find:
time for which box will remain in contact with spring
Solution: The time taken to complete one oscillation is called the time period. where m is the mass, and k is the spring constant.
Time period is given as
t = π √m/k
t = 3.14 √8/69
t = 1.1 sec
So time for which box will remain in contact with spring is 1.1 sec
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What relation can you state about the acceleration of the charge and it mass? Describe the mathematical relation, such as "directly proportional ", or "inversely proportional
Relation can you state about the acceleration of the charge and it mass is they are inversely proportional .
According to the question
Newton's second law :
Newton's second law is a quantitative description of the changes that a force can produce on the motion of a body. It states that the time rate of change of the momentum of a body is equal in both magnitude and direction to the force imposed on it.
F = m * a
a = [tex]\frac{F}{m}[/tex]
Relation can you state about the acceleration of the charge and it mass is
According to Newton's second law of motion, acceleration is inversely proportional to the mass when the force is a constant.
The acceleration is directly proportional to the force when the mass remains constant.
Hence, Relation can you state about the acceleration of the charge and it mass is they are inversely proportional .
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Why does the chord of an electric heater not glow while the heating element does
Answer:
The heating element of the heater is made up of alloy which has very high resistance so when current flows through the heating element, it becomes too hot and glows red. But the resistance of cord which is usually of copper or aluminum is very low so it does not glow.
Light described as what two things?
Answer:modeled as an electromagnetic wave. In this model, a changing electric field creates a changing magnetic field.
Explanation:
Interstellar dust is effective at blocking visible light because Choose one: A. the dust is so dense. B. dust grains are so small. C. dust grains are so large. D. dust grains are so few.
Answer: Interstellar dust is effective at blocking visible light because dust grains are so small.
Explanation: To find the answer, we need to know more about the interstellar dust.
What is interstellar dust?Interstellar dust developed from dying stars as they burn out.This dust can block the visible light as well as UV emerging from the stars, because dust grains can block light at optical wavelengths.it absorbs and scatters blue light more than red. thus, red light can pass through it.If we place a star behind the dust, it will look more redder than its usual color. This is called interstellar reddening.Grains have a typical size of [tex]10^-6 m[/tex].Thus, we can conclude that, Interstellar dust is effective at blocking visible light because dust grains are so small.
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What is the energy of an electromagnetic wave that has a wavelength of
7.0 x 10-12 m? Use the equation E= hc where hc = 1.99 × 10-25 J-m.
OA. 2.8 × 10-14 J
OB. 1.4 x 10-36 J
OC. 9.0 x 10-37 J
OD. 7.2 x 1035 J
SUBMIT
Answer:
A: 2.8 * 10^(-14) J
Explanation:
Formula to find the energy is;
E = hc/λ
Where;
E is energy of a photon (E)
λ is wavelength of the light
c is speed of light
Thus;
E = (1.99 *10^(-25))/(7 * 10^(-12))
E = 2.8 * 10^(-14) J
You're holding an open house for Brenda. Walt and Mary walk in and ask you for a flyer that gives details about the property. At this point, what's your relationship with Walt and Mary
Walt and Mary are my Customers at this point.
To construct proper client relationships you need to: greet clients and approach them in a way that is herbal and suits the character scenario. show customers that you recognize what their desires are. be given that a few humans may not want your merchandise and concentrate on constructing relationships with people who do.
Use the time period clients, with an apostrophe before the “s” to expose a possessive form for a single consumer. Use the time period clients', with an apostrophe after the “s” to show the possessive plural shape of a couple of patrons. Do now not use an apostrophe if there's no possessive indication needed.
The definition of a consumer is a person who buys services or products from a store, restaurant, or different retail vendor. An example of a patron is someone who is going to an electronics save and buys a tv. (Casual) a person, mainly one engaging in a few types of interaction with others.
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balance the equation
P + 02 → P205
Answer:
4P + 502 → 2P205
Explanation:
Hence the above equation is balanced.
Explanation:
[tex] \underline{ \underline{ \large{ \text{Given \: chemical \: equation}}}} : [/tex]
[tex] \tt{P \: + O _{2} \: \: \: \: ➞ \: \: P_{2} \: O_{5}}[/tex]Here , Multiply P2O5 by 2 and O2 by 5 to equalize oxygen :
[tex] \tt{P+ 5O_{2} \: \: ➞\: \: 2P_{2} \:O_{5}}[/tex]
Now , To equalize P atoms , Multiply P by 4
[tex] \boxed{ \large{\tt{ 4P + 5O _{2} \: ➞ \: \: \: \: 2P_{2} \: O_{5}}}}[/tex]
Here , On the left side we have 4P and On the right side ,we have 4P. Again , On the left side , we have 10 O and On the right side , we have 10 O. And yippie , we got the balanced chemical equation !!!
Hope I helped ! ♡
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A 2. 0mc charge in an external field of 20n/c, north (direction) will experience a force of: ___0. 04____________ newtons, the direction of the force is __north___________
2. 0 mc charge in an external field of 20n/c, north (direction) will experience a force of 0.4 newtons, the direction of the force is north
Force in an electric field = charge * electric field
given
charge = 2* [tex]10^{-3}[/tex] C
electric field = 20 N/C
Force in an electric field = 2* [tex]10^{-3}[/tex] * 20
= 0.04 N
since , external field is in north direction then the force must be in north direction because the direction of an electric field at a point is the same as the direction of the electric force acting on a positive test charge
hence, 2. 0 mc charge in an external field of 20n/c, north (direction) will experience a force of 0.4 newtons, the direction of the force is north
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An island reports that in the year 2000 there were 240 babies born. That same year, 100 individuals died.
What is the growth rate for this island?(Show your work and indicate if it is positive or negative.)
Answer:
+ 140
Explanation:
You can show the natural growth rate by subtracting the death rate from the birth rate during one year and converting this into a percentage.
Here it would be:
240 - 100 = + 140
// if you want to convert it to percentage, you need to know the size of the population
it would be
140 / (population size) * 100 %
Theoretically, what would be the mass of an object accelerated
to 100% the speed of light?
I know most of the answers will say infinity, but still this needs deeper look about its physical meaning and does it consider a practical logic?
Infinity usually used for something we could not measure, however the reality may be different!
The denominator of the equation would become 0 and the mass would become infinite if the mass's velocity ever surpassed the speed of light.
Speed of light and mass:The amount of energy needed to accelerate an infinite mass would be infinite as well. The fact that light travels at the speed of c indicates that it has no rest mass.
When a mass particle approaches the speed of light, its energy grows and becomes infinite at that speed, which is why it can never be accelerated to that speed.
Experiments have confirmed this, and it has been demonstrated that nothing goes faster than the speed of light.
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A radar receiver indicates that a pulse return as an echo in 20 μs after it was sent. How far away is the reflecting object? (c = 3.0 × 10^8 m/s)
A radar receiver indicates that a pulse return as an echo in 20 μs after it was sent. The reflecting object would be 3000 m away .
Phenomenon of hearing back our own sound is called an echo. It is due to successive reflection of sound waves from the surfaces or obstacles of large size. To hear an echo, there must be a time gap of 0.1 second in original sound and the reflected sound.
Given
time = 20 μs = 20 * [tex]10^{-6}[/tex] s
let distance to the reflecting surface be = x
total distance travelled by pulse will be = 2x
speed = 3.0 × [tex]10^{8}[/tex] m/s
distance = speed * time
2x = 3.0 × [tex]10^{8}[/tex] * 20 * [tex]10^{-6}[/tex]
x = 3000 m
The reflecting object would be 3000 m away
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A 65.0 kg skier slides down a
37.2° slope with uk = 0.107.
If the slope is 42.0 m long, and
the skier starts from rest, how
fast is she going at the bottom?
(Unit = m/s)
She is going at a velocity of 20.63m/s to the bottom.
Friction is a resistive force between a body and the surface it is moving over in mechanics. It is computed mathematically using the friction coefficient and normal force product.
The mass is: m = 65kg
The coefficient of friction is: μk = 0.107
The angle is: θ = 37.2°
W = mg
W₁ = W sin θ = mg sin θ
W = W cos θ = mg cos θ
[tex]F_{N} = W = mgcos[/tex]θ
[tex]F_{f} =[/tex] µ[tex]F_{N}[/tex] = µmg cosθ
[tex]F_{net} = W_{1} - F_{f}[/tex]
[tex]= mg sin[/tex]θ - µmg cosθ
[tex]F_{net} = ma[/tex]
[tex]ma =[/tex] mg sinθ - µmg cosθ
a = g sinθ - µmg cosθ
= 9.8 sin (37.2) - (0.107) 9.8 cos(37.2)
= 9.8 × 0.605 - 0.107 × 9.8 × 0.796
= 5.929 - 0.834
= 5.095 [tex]m^2/s[/tex]
∴ Δd = [tex]\frac{1}{2} a ([/tex][tex]t^2[/tex][tex])[/tex]
[tex]t^2[/tex] = 2Δd / a
[tex]t^2=[/tex] 2 × 42.0 / 5.095
[tex]t^2 =[/tex] 16.48
[tex]t=4.05[/tex]
∴ [tex]v_{2} = v_{1} + at[/tex]
[tex]= 0+ 5.095 (4.05)[/tex]
[tex]= 20.63 m/s[/tex]
Therefore, she is going at a velocity of 20.63m/s to the bottom.
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