a. Nyquist rate = 30 kHz is the Nyquist rate.
compact disc (CD) records audio signals digitally by means of a binary code. Assume an audio signal bandwidth of 15 kHz.
⇒ According to the Nyquist criteria, the sampling frequency must be at least 2 times the bandwidth.
⇒Nyquist rate = 2 x 15 kHz
⇒Nyquist rate = 30 kHz
So that means we need to take at least 30,000 sample/s to meet Nyquist criteria.
What exactly is the Nyquist rate?To accurately measure the Nyquist rate, multiply it by two. The theorem can be applied backwards. The Nyquist frequency, one-half the given sample rate, is the highest frequency that equipment of a given sample rate can reliably measure. The Nyquist theorem is a fundamental concept in information theory.Nyquist specifically states that in a noise-free channel, we can transmit data at a rate of up to. C=2Blog2M. bits per second, where B denotes the bandwidth (in hertz) and M denotes the number of signal levelsTo determine the Nyquist frequency for your system, divide the sampling rate by two. For example, if your system's sampling rate is 10 Ms./s (10,000,000 samples per second), your system's Nyquist frequency will be 5 MHz's
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A skydiver with a mass of 70 kg accelerates to Earth at a rate of 9.8 m/s2 due to gravity. What is the force on the skydiver? Explain how you determined the answer and its units.
Explanation:
GIVEN DATA
Mass=70kgAcceleration =9.8m/s2RTF=Forcesince P(momentum)=Mass×Velocity
SOLUTIONFROM NEWTONS SECOND LAW OF MOTION ,F = △P(change in momentum) t(time)F = P2 -P1
t
F= Mv2-Mv1
t
F=M( v2-v1) ,(a=v2-v1)
t t
F= m×aF= 70 × 9.8F= 686 N
ANSWER EXPLANATION IN WORDS
That question is related to Newton's second law of motion, the question ask you to find the force it gives you a mass and a acceleration As we know that the SI unit of acceleration is newton per kilogram or metre per second square It is correct to write metre per second square instead of Newton Per kilogram because because all of them are the SI unit of acceleration so that is the answer we get 686 Newton by Force .
How do atoms behave in cold and hot temperatures
In cold:
An object's temperature is a measure of how much its atoms move — the colder an object is, the slower the atoms are.
In heat:Heating a substance makes its atoms and molecules move faster. This happens whether the substance is a solid, a liquid, or a gas.
How much metabolic energy must a bird of mass 200 g expend to fly to a height of 20 m? neglect all losses due to friction, physiological imperfection, and the acquisition of kinetic energy.
The amount of metabolic energy expended by the bird is 39.2 J.
What do you mean by energy?Energy is the ability to perform work in physics. It might exist in several different forms, such as potential, kinetic, thermal, electrical, chemical, radioactive, etc. Additionally, there is heat and work, which is energy being transferred from one body to another. Energy is always assigned based on its type once it has been transmitted. Thus, heat transmitted may appear as thermal energy while labor performed may result in mechanical energy. Motion is a property of all energy types. For instance, if a body is moving, it possesses kinetic energy. Even while at rest, a tensioned object like a spring or bow has the ability to move; this is due of its design, which includes potential energy.
E = mgh = (0.20)*(9.8)*(20) = 39.2 J
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How long will it take for 10% of the u−238 atoms in a sample of u−238 to decay?
it will take around 1,448 billion years for U-238 atoms to decay.
What are radioactive materials?When a radioactive nucleus spontaneously releases excess energy, that energy is referred to as ionizing radiation. radiation from ions may manifest as alpha or beta particles. either gamma rays or particles. The action of Radioactive means to emit radiation.
U-238 has a radioactive half-life of 4.5 billion years, which is independent of the original concentration.
c₀ - initial concentration of U-238.
c - concentration of U-238 remaining at the time.
t = 4,5·10⁹ y.
First, calculate the radioactive decay rate constant λ:
λ = 0,693 ÷ t = 0,693 ÷ 4,5·10⁹ y = 1,54·10⁻¹⁰ 1/y.
ln(c/c₀) = -λ·t₁.
ln(0,8/1) = -1,54·10⁻¹⁰ 1/y · t₁.
t₁ = 1,448·10⁹ y.
Therefore, it will take around 1,448 billion years for U-238 atoms to decay.
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The density of aluminum is 2700 kg/m3. if transverse waves propagate at in a aluminum wire, what is the tension on the wire?
The tension on the wire is 52.02N.
Using the formula:
[tex]v = \sqrt{\frac{T}{u} }[/tex]
where, v = speed of sound wave
T = tension in wire
μ = mass per unit length
The area of aluminium wire is : [tex]\frac{\pi d^{2} }{4}[/tex]
Area = 1.66×[tex]10^{-5}[/tex][tex]m^{2}[/tex]
and μ = ρA = 2700×1.66×[tex]10^{-5}[/tex]
μ = 0.045kg/m
Therefore, tension is :
[tex]v = \sqrt{\frac{T}{u} }[/tex]
[tex]34^{2} = \sqrt{\frac{T}{0.045} }[/tex]
Solving for T we get, T = 52.02N.
Therefore, the tension on the wire is 52.02N.
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Suppose you measured the acceleration due to gravity and got a value of 10.1 m/s2. if the accepted value is 9.81 m/s2 , what is the percent error in your measurement (absolute value only)?
The percent error in your measurement is 2.95 % error.
here it is for the reason that the actual value is 9.81 [tex]m/s^{2}[/tex].
And the calculated value is 10.1 [tex]m/s^{2}[/tex].
Error = 10.1-9.81
= 0.29
Now percentage error = [tex]\frac{0.29}{9.81}*100[/tex]
= 2.95 %
So, the required error is 2.95 percent.
To degree the percent errors within the given records we should have the idea of percent and error calculation.
To measure the error we should calculate the difference in the real price and the calculated fee.
And to calculate the proportion we ought to divide the received error cost by using the actual price and multiply by means of a hundred.
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a car has wheels with a 12 inch radius. if each wheel's rate of turn is 5 revolutions per second, find the angular speed in units of radians/second.
The angular speed of the car's wheel in units of radians/second is determined as 31.42 radian per second.
Angular speed of the car's wheel
The angular speed of the car's wheel is calculated as follows;
ω = 5 rev/sec
Convert the angular speed in revolutions per second to radian per second.
ω = 5 rev/sec x 2π rad/rev
ω = 10π rad/sec
ω = 31.42 rad/sec
Thus, the angular speed of the car's wheel in units of radians/second is determined as 31.42 radian per second.
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if a subway train is moving to the left and then comes to a stop, what direction is the acceleration
The subway train is moving to the left and then comes to a stop, what direction is the acceleration will be towards right and will be positive.
The train comes to a stop, this means that the velocity gradually decreases. Hence, the acceleration must be positive and points towards the right.
velocity and acceleration:
velocity is the charge of alternate inside the position of an object, at the same time as acceleration is the rate of trade of the fee. consider the movement alongside a line. If the velocity and acceleration are in the same route, then the charge constantly will growth in time. inside the meantime, if the speed and acceleration are in contrary instructions, then the rate steadily decreases to 0 speed, reverses route, and now the velocity is in the identical path of the acceleration.
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State the sub particles of atoms and name and change
Answer:
proton = charge is + (positive charge)
neutron = charge is 0 ( no charge - neutral)
electron = charge is - (negative charge)
hope this is what you meant :)
If a rolling ball had 18 joules of KE and is rolling 3 m/s, what is the mass?
Answer:
4Kg
Explanation:
1/2mv²=K.E
1/2m×3²=18J
1/2m×9=18
9m=18×2
9m=36
m=36/9
m=4Kg
Answer:
F=MA FORSE= MASS X ACCELERATION
Explanation:
So the answer should be 54 as 18 X 3 = 54
( I read the question wrong)
The writer is considering adding the following sentence after sentence 9. Indeed, kane persuasively argues that diplomacy works best "if we bring it down to our individual communities and the people in the communities. " should the writer add this sentence after sentence 9 ?.
Yes, because it incorporates a second clarifying quotation from the expert, adding more weight to the argument presented in phrase 9.
Within a group of diplomats, negotiations and bargaining essentially consist of trying to get more than you are likely to get by negotiating, and eventually reaching a compromise. On occasion, foreign officials will join ongoing negotiations for assistance. Because it advances the interests under its purview and strengthens nations, states, and organizations, diplomacy is significant. The primary tool of foreign policy, which stands for the more general objectives and plans that direct a state's relations with the rest of the world, is diplomacy. Diplomatic negotiations and processes typically lead to international treaties, accords, alliances, and other manifestations of foreign policy. Diplomats may also provide government with advice to assist form a state's foreign policy.
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how far would it be from the milky way galaxy to the most distant galaxies in the observable universe on this scale?
The two marbles are separated by around 133 m or 30 vehicle lengths.
It is possible to determine the distance between our marble and the most distant galaxies in the universe by first comparing the size of the Milky Way Galaxy to that of a marble.The Milky Way Galaxy is just around 2,000 LY (Light Years) thick and roughly 100,000 LY (Light Years) wide.
Let's continue using the conversion of:
1 cm = 100,000 LY
The Andromeda and Triangulum galaxies are two of the noteworthy members of the Local Group, a collection of galaxies nearby to our own. On this scale, we can assume that distance from Earth and distance from the edge of the Andromeda Galaxy are approximately 2.5 MLY (2.5 Million Light Years) apart.The galaxy spans about 220,000 LY. So let's determine where to place this marble:
2,500,000/100,000 = 25 cm
We may lay a marble to symbolise the Andromeda Galaxy that is nearly twice the size of our Milky Way Galaxy marble at 25 cm.
We can see farther as our observational equipment advances. A galaxy 13.3 BLY distant is the furthest object Hubble can currently observe .
So let's try placing the marble here:
13,300,000,000/100,000 = 13,300cm = 133m
To put this into context, the two marbles are separated by around 30 vehicle lengths.
See the reference pic below:
The complete question is: In a scale model of the Local Group of Galaxies, in which the Milky Way Galaxy was the size of a marble (about 1 cm in diameter), how far would it be from the Milky Way Galaxy to the most distant galaxies in the observable universe on this scale?
Find the resultant of the following forces: (a) 425 newtons at 55 degrees; (b) 5 newtons at 161 degrees; (c) 35 newtons at 320 degrees.
consider F1 = 425 N θ1 = 55
F2 = 5 N θ2 = 161
F3 = 35 N θ3 = 320
Now, take x and y component of force
Fx = F1cos55 + F2cos161 + F3 cos320
fx= 425 * 55 + 5 * (-0.94) + 35 * 0.76
fx =242.2- 4.7+ 26.6
fx =264.1
now fy
Fy = F1sine55 + F2sine161 + F3 sine320
fy= 425 * 0.81 + 5 * 0.32 + 35 * (-0.64)
fy = 344.2+1.6-22.4
fy = 323.4
now resultant force
Fr^2= fx^2+fy^2
= (264.1)^2 + (323.4)^2
Fr= 417
now, consider F1 = 425 N θ1 = 55
F2 = 5 N θ2 = 161
F3 = 35 N θ3 = 320
Now, take x and y component of force
Fx = F1cos55 + F2cos161 + F3 cos320
fx= 425 * 55 + 5 * (-0.94) + 35 * 0.76
fx =242.2- 4.7+ 26.6
fx =264.1
now fy
Fy = F1sine55 + F2sine161 + F3 sine320
fy= 425 * 0.81 + 5 * 0.32 + 35 * (-0.64)
fy = 344.2+1.6-22.4
fy = 323.4
now resultant force
Fr^2= fx^2+fy^2
= (264.1)^2 + (323.4)^2
Fr= 417
now, resultant angle
tan θ =fy/fx
= 323.4/264.1
tan θ = 1.2
θ =0.020
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What is the length of RG, if PR=2 and PG=16? P R G
The length of RG, given the data from the question is 14
Data obtained from the questionFrom the question given above, the following data were obtained:
Length of PR = 2Length of PG = 16Length of RG =?How to determine length of RGWe can obtain the length of RG as illustrated below:
Length of PG = Length of PR + Length of RG
Thus,
Length of RG = Length of PG - Length of PR
Length of RG = 16 - 2
Length of RG = 14
Therefore, we can conclude that the length of RG is 14
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A cyclotron with a magnetic field of 0.36 t is designed to accelerate protons in a circle with a radius 0.56 m. what is the angular frequency of the proton? answer in units of rad/s.
The angular frequency of the proton which is cyclotron with a magnetic field of 0.36t is 4.31 x 10⁷ rad/s .
What is magnetic field ?The electromagnetic force, one of the four fundamental forces of nature, is the origin of the magnetic force, which is produced by the movement of charges. Any two charge-containing objects travelling in the same direction are attracted to one another magnetically.
The electromagnetic force, one of the four basic forces of nature, produces the magnetic force, which is caused by the movement of charges. A magnetic attraction draws two charge-containing objects together when they are moving in the same direction.
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Suppose you take trips that covers180km and take 3hours to make your average speed is
Explanation:
average speed= distance/time
=180÷3
=60 km/h
If 2 objects at different temperatures are in contact with each other what happens to their temperature
When two objects of different temperatures come into contact with each other, equilibrium is reached and energy is transferred from the hotter object to the cooler object until the objects reach thermal equilibrium (that is, they are at the same temperature).
When one object heats another, the increase in the temperature of one object is not always the same as the decrease in the temperature of the other, because the specific heat of one object is higher than the other.
Objects exchange thermal energy until they are at the same temperature. When two objects with different temperatures come into contact, they eventually achieve the same temperature. This is because of the thermal equilibrium.
Heat Transfer: Heat Transfer from Warmer Object to Cooler Object - When two substances at different temperatures are mixed, heat is transferred from a hotter object to a cooler object until the same temperature is reached (zero law of thermodynamics) - thermal equilibrium).
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a loudspeaker at the origin emits a 130 hz tone on a day when the speed of sound is 340 m/s. the phase difference between two points on the x-axis is 5.2 rad .
According to the given question distance between these two points is 1.971m.
What do you mean by distance?The distance can be a literal length as defined by physics or a general estimation based on other variables. It is a generalization of the idea of physical distance. Distance is a non-numerical unit of measurement in psychology and the social sciences; psychological distance is the separation of an object from itself along dimensions including time, space, and isolation.
According to the question:
speed=frequency*wavelength
wavelength = 340/140 =2.428 m
phase difference=2pi× x/lamda
x=5.1*2.428/(2*pi)
x=1.97m
since v= f × wavelength
where v = speed of sound and f = frequency
therefore wavelength = v/f = (340)/140 = (17/7)m
now, since Phase angle = (2×pi/wavelength)×shift
or, shift = phase angle × (wavelength/2×pi) = 5.1 × ((17/7)/2×pi) = 1.971m
Hence, the distance between these two points = 1.971m
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The advantage of using the scientific method is that
A: it's cautious building of evidence-based understanding is dependable and logical.
B: it's random way of trying everything covers all options
C: any evidence in disagreement with a theory can be thrown out.
D: continual testing leads to mistakes being made.
The correct option is A.
The advantage of using the scientific method is that it is having a well-cautious building of evidence-based understanding that is dependable and logical.
The scientific method includes rigorous observation in addition to logic as a system of reasoning for organizing but for deducing beyond what is known from observation. Induction, prediction, and analogy are only a few examples of different reasoning techniques.
Evidence, as used in legal contexts, is generally defined as information, facts, or data that supports (or refutes) a claim, assumption, or hypothesis. In reality, anything could qualify as proof provided it is deemed to be true, trustworthy, and pertinent.
Although scientists frequently utilize evidence in other ways, such as when applying ideas to real-world issues, scientific evidence is evidence that helps to either support or refute a scientific theory or hypothesis.
Generally speaking, scientific evidence is founded on the knowledge that has been acquired via the application of the scientific method. This indicates that the evidence's underlying assumptions have undergone testing and general acceptance in the scientific community.
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CA-Common Core English Language Arts 9 A
Answer:
The standards establish guidelines for English language arts (ELA) as well as for literacy in history/social studies, science, and technical subjects.
Explanation:
Answer:
A
Explanation:
what is the number of waves here?
Answer: i counted 10 waves on your graph
Explanation: hope this helps!!!
Answer:
The Number of waves is 9 based on the trough and crest.
determine the design angle ϕ ( 0 ° ≤ ϕ ≤ 90 ° ) ϕ(0°≤ϕ≤90°) between members ab and ac so that the 400-lb horizontal force has a component of 600 lb which acts up to the right, in the direction from b toward a. also calculate the magnitude of the force component along ac. take
The magnitude of the force along ac is 322.97 lb and the design angle of the system is ϕ = 38.26°
The Given problem can be solved on the Parallelogram law of vector addition and law of sines,
from the figure, we can write
F = √(400² + 600² - 2(400 × 600)cos 30)
F = 322.97 lb
In order to get the design angle, we will solve by:
(sinϕ)/(sin 30) = 400/322.97, where ϕ is the design angle.
therefore
sinϕ = (400/322.97) × sin 30
sinϕ = 1.2385 × 0.5
sinϕ = 0.61925
ϕ = sin^(-1) 0.61925
ϕ = 38.26°
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a computer's power supply converts mains ac to low-voltage regulated dc power for the internal components of a computer. you are building a new computer. you are deciding which type of power supply to install. which of the following definitions best describes a valid type of power supply?
In order to prevent overloading of any circuit, dual rail electrical supply includes independent tracks and P C B traces that are used to offset voltage sags between various circuits.
Using conductive paths, tracks, or signal traces etched from copper sheets laminated onto a non-conductive substrate, a printed circuit board, or PCB, is used to mechanically support and electrically link electronic components.
Semiconductors are used by practically all inverters to generate a controlled power output. An input voltage is rectified if the source has an ac input.
It is, therefore, the proper response.
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receptacles have several screw terminals for the attachment of circuit conductors. match the following screws with their intended conductor.
A. Equipment grounding conductor B. Hot (phase) conductor C. Grounded (white) conductor
Matching is done as:Silver-colored screw is matched with C) Grounded (white) conductor
Brass-colored screw is matched with B) Hot (phase) conductor
Green hexagonal screw is matched with A) Equipment grounding conductor.
Electrical conductorA substance or material that permits the flow of electricity is known as an electrical conductor.
What are the three different types of conductors?When a voltage is applied, electrical charge carriers, typically electrons or ions, move easily from atom to atom.
Are conductors a component of a circuit?There are four different types of conductors: good conductors, semiconductors, resistors, and non-conductors.
Metals are effective electrical conductors. One or more loosely bonded valence electrons, or even just one, can be found in metals. These electrons can freely flow around an electric circuit, creating a domino-like effect.
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the length of the eye and the curvature of the cornea determine the refractive error of an eye. hyperopia, or farsightedness, is produced by a shorter-than-normal eye.
True, the length of the eye and the curvature of the cornea determine the refractive error of an eye. Hyperopia, or farsightedness, is produced by a shorter-than-normal eye.
What is Hyperopia?With farsightedness (hyperopia), a common visual issue, you may be able to see far objects clearly but have hazy vision of nearby items.
Your ability to focus is influenced by how farsighted you are. People with severe farsightedness might only be able to see objects that are far away clearly, whereas people with mild farsightedness might be able to see objects that are nearby clearly.
SymptomsBeing farsighted can mean:
Nearby objects might seem hazy
Squinting is required to see clearly.
You experience eye pain or discomfort around the eyes as well as eyestrain.
After performing close work, such as reading, writing, using a computer, or sketching, for a while, you have general eye discomfort or a headache.
A distortion of focusYour cornea or lens must be uniformly and smoothly bent to allow light to pass.
You have a refractive error if your cornea or lens are not uniformly and smoothly curved, which causes improper light refraction.
When your cornea is overly flat or your eyeball is shorter than normal, you develop farsightedness. Nearsightedness has the opposite impact.
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How does the working distance of a microscope chnage when you increase the magnification?
By switching to a higher power objective lens, the working distance is shrunk while the overall magnification increases.
What is working distance of a microscope?
Working distances for high-power oil immersion objectives can be as low as 0.1 mm and as high as 50 mm for dissecting or stereo microscope objectives. As magnification, resolution, and numerical aperture rise, it falls. Most microscope objectives are made with limited operating distances in mind.
By switching to a higher power objective lens, the working distance is shrunk while the overall magnification increases. On the other hand, lowering the total magnification while extending the working distance by adding a reduction objective.
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(15 points) a 4000-w electric resistance heater is heating water in an insulated, constant diameter tube. if the water enters the heater steadily at 315 k and leaves at 360 k, determine the mass flow rate of water in kg/s.
The mass flow rate of water is 0.087 Kg/s.
Contact tube diameter means no pressure head drop.
P=C heating done at P=C.
MC(T₁ - T₂) = Q = W
M × 1.015 (360-315) = 4000
M = 4000 / 1.015 × [tex]10^{3}[/tex] × 45
M = 0.087 Kg/s
Pressure is defined due to the fact the pressure of all the gasoline particle/wall collisions divided thru the vicinity of the wall: All gases exert strain ; it's far one of the important measurable portions of this phase of depend.
From the weather to air tour, strain performs a dramatic position in our lives. It plays especially vital roles at some point of chemical reactions. through manipulating stress, chemists can pressure chemical reactions to occur and the transitions among solids, beverages, and gases to boost up.
The primary unit of pressure is the pascal, described because the stress exerted with the useful resource of a pressure of one newton perpendicularly upon a place of one square meter.
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what is the wavelength of an earthquake that shakes you with a frequency of 11.1 hz and gets to another city 93.0 km away in 14.0 s?
The correct answer is 598.4m
Two key elements in describing a wave's nature are its wavelength and frequency. Wavelength is essentially a measurement of the separation between two adjacent wave crests or troughs. It is always calculated in the direction of the wave, and the sign for it is. Given that it is a measurement of distance, it is stated in terms of metres.
Frequency: The number of times a particle vibrates during a sound wave's passage through a medium is referred to as frequency. The total amount of vibrations that occur within a certain period of time is the frequency.
Wavelength: The distance between two successive curve crests or troughs is known as a wavelength. The distance between the crests and troughs of a high-frequency wave is smaller than that of a low-frequency wave, and vice versa.
s=93km=93000m
f=11.1hz
t=24.43 sec
λ=v/f
λ=s/ft
λ=93000/(11.1)(14)
λ=93000/155.4
λ=598.4m
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An unmanned satellite orbits the earth with a perigee radius of 10,000 km and an apogee radius of 100,000 km. at how many locations in the orbit is the altitude 10,000 km?
At one location in the orbit, the altitude is 10,000 km.
What do apogee and perigee mean?Its perigee is the monthly location where it comes closest to Earth (this varies throughout the year).
The Moon’s apogee is the location where it is each month when it is the furthest away from Earth (this varies throughout the year as well).
What is the Earth’s apogee?The location on an object’s orbit around the earth that is furthest from the planet’s core, such as a satellite.
The distance at which an object orbiting a planet or satellite (like the moon) reaches that point.
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How much work have you done when you lift a 90-N child 0.5 m
Answer: not alot
Explanation: