The tension in the supporting cable when the cab originally moves downward is 18422.4 N
What is tension?
Tension is described as the pulling force by the means of a three-dimensional object.
Tension might also be described as the action-reaction pair of forces acting at each end of said elements.
Here,
m =combined mass = 1600 kg
s = Displacement of the elevator = 42 m
g = Acceleration due to gravity = 9.81 m/s²
u = Initial velocity = 12 m/s
v = Final velocity = 0
According to the equation of motion:
[tex]v^{2} - u^{2} = 2as[/tex]
0 - 12^2 = 2*a*42
a = - 144 / 84
a = - 1.714 m/s^2
Now let's write the equation of the forces acting on the elevator. Taking upward as positive direction:
T-mg = ma
T = m(g-a)
T = 1600 ( 9.8-(-1.74))
T=18422.4 N
Hence,
The tension in the supporting cable when the cab, originally moving downward is 18422.4 N
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A pool cue ball moving at 2.1 m/s east collides in a straight line with the eight ball at rest. (You may assume that the cue ball and the eight ball have the same mass.) Find the velocity of the eight ball after the collision if momentum is conserved and
the cue ball stops
the cue ball continues on in the same direction at 0.10 m/s
the cue ball continues on in the same direction at 0.70 m/s.
1. 2.1 m/s west.
2. 2.0 m/s west.
3. 1.4 m/s west.
Momentum is a conserved quantity, meaning that it is neither created nor destroyed. This means that the total momentum of the system (cue ball and eight ball) before and after the collision must stay the same. After the collision, the momentum of the system is equal to the momentum of the eight ball alone since the cue ball no longer has momentum after it stops (for option 1) or has a different momentum depending on its speed (for options 2 and 3).
Since momentum is mass times velocity, we can solve for the velocity of the eight ball by rearranging this equation:
Momentum = Mass x Velocity
Velocity = Momentum / Mass
Plugging in the given values:
1. Velocity = (2.1 m/s east) / (mass of both balls) = 2.1 m/s west
2. Velocity = (2.1 m/s east + 0.10 m/s east) / (mass of both balls) = 1.9 m/s west
3. Velocity = (2.1 m/s east + 0.70 m/s east) / (mass of both balls) = 1.4 m/s west
A Physical Education (gym) class is playing a game of soccer. During the game, the ball experiences a net force of 0 newtons. Which statement explains what is most likely happening with the ball?
A. It is sitting still.
B. It is bouncing off someone’s knee.
C. It has been kicked across the field.
D. It has been tossed straight up into the air.
When, During the game, the ball experiences a net force of 0 newtons. It is sitting still is the statement explains what is most likely happening with the ball.
What is Net force ?The vector sum of the various or single forces exerted on a particle or object is termed as the net force. The original force's affect on the motion of the particle the force is exerted is replaced by the net force, which is a single force.
Newton:As per the International System of Units, the unit of force is the newton. The force that causes a mass of one kilogram to accelerate by one metre per second is what we call as 1 kgm/s2. It bears Isaac Newton's name in honor of his major contributions to classical mechanics, particularly Newton's second rule of motion.To know more about net force visit
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a mechanical wave transmits energy through a vacuum. true or false?
Answer:
False
Explanation:
False ... a mechanical wave needs a medium of particles to propagate....a vacuum has no particles
If you apply a force of 10 n to a box and push it 10 m in 10 s, how much power did you deliver?.
According to the given statement 10W power did you deliver.
What is power?Power is the rate at which energy is transferred, transformed, or converted. It is a measure of the amount of work that can be done in a given amount of time. In physics, power is the product of the time rate of change of energy, or the rate of doing work. Power is measured in watts or joules per second (J/s). It is an important concept in many fields, such as mechanics, thermodynamics, electromagnetism, and nuclear physics. It is also used to measure the capacity of machines, devices, and systems to perform work.
Force=10N
Distance =10m
Time=10s
Power =?
But Power= Work done/Time taken
P= W/s
W= F x d=10x10=100
P=100/10
P=10W
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When is there a decrease in air pressure on top of a plane's wing?
A)as the plane's speed decreases
B)as the plane's fuel runs low
C)as the plane's speed increases
Answer: Option C.
Explanation:
As the speed of plane increases and it moves forward it allows to push air on the bottom of the wings of the plane which results in increasing the pressure
The fact of air pressure on top of planes wing decreases with the increase bin plane's speed is based on Bernoulli’s Principle which states that with the fast moving air, the pressure decreases.
Therefore,n when the plane moves up it's wing pushes air down and on the same time the air pressure decreases at the top of the wing, this difference between the high and low pressure allows the flight to lift up.
Hence, the correct option is C.
A car leaves a city with a speed of 90 mph. Three hours later and out of the same city another car in pursuit of the first leaves with a speed of 120 mph. Find the time it takes for the second car to reach the first.
Answer:
9 hours
Explanation:
When the 2nd car catches up to the first, both cars will have gone the same distance.
Distance = rate x time
Distance car 1 traveled when car 2 catches up = 90 mph(3 hr + t)
Distance car 2 traveled when it catches up to car 1 = 120t
90(3 + t) = 120t
270 + 90t = 120t
30t = 270
t = 270/30 = 9 hrs
Therefore, 12 hours after car 1 leaves the city and 9 hours after car 2 leaves the same city, they meet up.
To prove it:
90(12) = 120(9) = 1080 Car 2 catches up to Car 1 1080 miles from the city
A 2 kg book is sitting on a table. A 10 n force is pulling to the right. A 3 n force is pulling to the left. What is the net force acting on the book?.
The net force acting on the book is 7N right.
The net force is defined as the total of all forces exerted on an object. Net force is essential since it aids in describing the motion of an item and can be used to calculate acceleration. The first law of motion of Isaac Newton states that an object in motion will remain in motion and an object at rest will remain at rest unless acted upon by a net force that is imbalanced. This indicates that knowing the net force acting on an object will aid in predicting its velocity.
In this case, we are given that:
Force F1 = 10 N pulling to the right
Force F2 = 3 N pulling to the left
Let's assume the right is positive and the left is negative.
To calculate the net force, we can use this following formula:
Fnet = F1 + F2
Fnet = 10 + (-3)
Fnet = 7
As the result, the net force would be 7 N.
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A block with the mass of 14.26kg is on a ramp with an incline of 41 degrees. If the block is stationary, what is the minimum value of the coefficient of static friction? [Please explain to me how you did it, I'm giving you 50 points lol the last two times I've asked ive gotten either no explanation or a link to a calculator...]
The minimum value of the coefficient of static friction is 1.33.
What is the coefficient of static friction?To calculate the minimum value of the coefficient of static friction, we need to determine the force of static friction acting on the block. The force of static friction is equal to the force of gravity acting on the block (mg) multiplied by the coefficient of static friction (µs
m = 14.26kg
θ = 41°
g = 9.8 m/s²
The force of gravity acting on the block is given by the formula:
Fg = mg
where,
m = (mass of the block)
g = (acceleration due to gravity)
Fg = 14.26kg *9.8 m/s²
Fg = 139.75 N
The force of static friction can be found using the formula:
Fstatic = µs * N
where,
µs = coefficient of static friction (unknown)
N = Normal force acting on the block
The normal force acting on the block is equal to the force of gravity acting on the block perpendicular to the ramp.
N = mg * cos(θ)
where,
θ = 41 degrees (incline of the ramp)
N = 14.26kg * 9.8 m/s² * cos 41°
N = 105.47 N
So,
Fstatic = µs * (mg * cos(θ))
making µs subject of the formula and substituting already calculated vaues we get,
µs = Fstatic
(mg * cos(θ))
µs = 139.75 N
105.47 N
µs = 1.33
This is the minimum value of the coefficient of static friction.
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A 5. 0 kg object, initially at rest, is acted on by a net force of 3. 0 s. During that time the object moves.
The distance moved by an object when it acted by a net force 1 N and time 3s is found to be 0.9m
Why is mass acceleration due to net force?According to this, an object's rate of change in velocity is directly proportional to the force used and moves in the direction of the applied force. The equation: summarises it. Mass (kg) times acceleration (m/s2) equals force (N). A constant mass item will therefore accelerate in direct proportion to the force exerted.
F = ma
acceleration = F/m => 1/5
v= u + at, u=0 (initially at rest);
v=at = distance/t = at;
S = distance => ut + 1/2at^2
=> 0 + 1/2 x 1/5 x 9 => 0.9m
the distance traveled by object in the given time 3s = acceleration x t2
How is acceleration calculated?The acceleration is determined by dividing the net force by the mass. An object's acceleration doubles if the net force exerted on it also doubles. Increased mass will result in a halving of acceleration. If the mass and net force are both doubled, the acceleration will remain constant.
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A net force of 1.0 N acts on a 5.0-kg object, initially at rest, for 3.0 seconds. What is the distance the object moves during that time?
A large telescope of mass 8410 kg is in a circular orbit around the earth, making one revolution every 927 minutes. What is the magnitude of the gravitational force exerted on the satellite by the earth? (G = 6.67 × 10-11 N ∙ m2/kg2, Mearth = 6.0 × 1024 kg)
The Earth's gravitational pull on the satellite is 651.8 N. Consequently, the satellite's gravitational pull on Earth is 651.8 N. As a result, the spacecraft accelerates at a rate of 1.5 m/s2.
Why does a satellite in a circular orbit not feel the effects of gravity?Centripetal force is used to maintain an object moving in a circle due to gravity. Since gravity always behaves perpendicular to motion, it has no effect on an item in a circular orbit.
Calculation:Mass of Telescope= 8410 kg
revolution in minutes = 927
G = 6.67 × 10-11 N ∙ m2/kg2
Mass of earth = 6.0 × 1024 kg
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HELP PLEASE HELP PLEASE
Which statement best summarizes the information in the paragraph? Earthquakes may occur at all types of plate boundaries. The strength of an earthquake depends on the type of boundary. All earthquakes at plate boundaries result from forces underneath Earth’s surface or volcanic eruptions. Different types of plate interactions result in earthquakes of varying strengths at various depths.
Different types of plate interactions at plate boundaries can cause earthquakes of varying strengths, at various depths, which can be caused by both forces underneath Earth's surface and volcanic eruptions.
What is plate interaction?Plate interactions refer to the forces and mechanisms that cause the movements and interactions of the Earth’s plates. These interactions are driven by convection currents in the Earth’s mantle, which are generated by the heat energy released by the Earth’s core. The plates move in different directions, resulting in different types of plate interactions. The most common type of plate interaction is called divergent boundaries, which occur when two plates move away from each other.
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Answer: D
Explanation:
A person pulls a sled along a flat snowy surface, dragging it with a rope. The rope makes a 20-degree angle with the ground. How much work does the person do on the sled if she drags it for 125 meters with a force of 70 N?
The person will do 8222.3 Joules of work on the sled if she drags it.
What does "work" mean in physics?Work is a physics term used to describe the energy transfer that takes place when an object is moved over a distance by an external force, at least some of that is applied in the direction of the displacement.
Given, angle made by the rope θ = 20°
displacement, s = 125m
force, F = 70N
Positive work is done by the force's displacement-direction component.
W = Fcosθ.s
W = 70N(cos20°)125m.
W = 8222.3 Joules
Since it is perpendicular to the distance, the force's vertical component does NOTHING. In other words, it is ineffective at moving the sled. Since it is the horizontal component of the force that moves the object, it is effective.
The person will do 8222.3 Joules of work on the sled if she drags it.
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A convex mirror forms an image of half the size of the object. When it is moved 15 cm away from the object, the size of the image becomes 2/5 times the size of object. Find the focal length of convex mirror. Answer is 30.
Answer:
focal length = 30 cm
Explanation:
You want the focal length of a convex mirror when moving the mirror an additional 15 cm away from the object causes its image size to decrease from 1/2 to 2/5 the size of the object.
Mirror equationThe relation between focal length (f), object distance (do) and image distance (di) is ...
1/f = 1/do +1/di
The ratio of heights is the same as the ratio of distances:
hi/ho =di/do
ApplicationIf we let do represent the original object distance, then (1/2)do = di, the original image distance. This gives one equation we need:
1/f = 1/do +1/(1/2do) = 3/do
Moving the mirror increases the object distance to (do+15). Now, the equation becomes ...
1/f = 1/(do+15) +1/(2/5(do+15)) = 7/(2(do+15))
SolutionSubstituting for 1/f, we have ...
3/do = 7/(2(do +15))
6(do +15) = 7do . . . . . . . . . cross multiply
90 = do . . . . . . . . . . . . subtract 6·do
Then the focal length is ...
1/f = 3/do
f = do/3 = 90/3 = 30
The focal length of the mirror is 30 cm.
a 415-kg container of food and water is dropped from a airplane
Since the object is experiencing free fall, if you ignore air resistance, the time it will take the container to fall 300m to the ground is 7.82 seconds.
What is free fall?Any motion of a body in which gravity is the only force acting on it is referred to as free fall.
The object dropped from the airplane is experiencing free fall.
Ignoring air resistance, the only force acting on the container is the force of gravity which accelerate the container by a constant value.
The time taken for the object to reach the ground is determined using the formula of an object experiencing free fall as given below:
s = ut + ¹/₂gt²
where
h is the height above the ground = 300 m
u is the initial vertical velocity of the container and is equal to zero since the object starts from rest.
g is the acceleration of gravity = 9.8 m/s²
t is the time = ?
The equation above becomes;
h = ¹/₂gt² since u is zero
Solving the equation for t:
t = √2h/g
t = √2 * 300 / 9.8
t = 7.82 seconds.
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Complete question:
A 415-kg container of food and water is dropped from an airplane at an altitude of 300m. First, consider the situation ignoring air resistance. Then calculate the more realistic situation involving a drag force provided by a parachute.
1. If you ignore air resistance, how long will it take the container to fall 300m to the ground?
Rock dropped from 18.16 m above the ground how fast will traveling when it reaches the ground
Answer: The Rock will be traveling at 5.93 m/s or around 21.4 km/hr or 13.3 mi/hr when it reaches the ground. (you can use go0gle to convert the speeds to something else, if needed)✅
PLEASEE GIVE BRANLIEST!!!
Explanation: ✅
The speed of the rock when it reaches the ground can be calculated using the equation:
v = √(2gh)
where v is the velocity, g is the acceleration due to gravity (approximately 9.8 m/s^2 on Earth), and h is the height from which the rock is dropped.
So, the speed of the rock when it reaches the ground will be approximately:
v = √(2 * 9.8 * 18.16) = √(35.1328) = 5.93 m/s
It will be traveling at 5.93 m/s or around 21.4 km/hr or 13.3 mi/hr when it reaches the ground.
The creator of the diagram above considers gerrymandering to be "stealing an election." How do the maps exemplify this?
OA. Map A is fair to members of the Red Party.
OB. Map B is fair to members of the Blue Party.
O C. The maps show representation that is proportional to the voters registered with each party.
O D. Both maps give disproportionate representation to the party that had the power to draw the lines.
M
31
DELL
District-based voting is used to choose representatives in Congress, state legislatures, and many county and municipal positions. In contrast, populations shift. Depending on the district, folks may move in or move out. The demographics of districts may also shift.
Option C is correct Answer.
Why does redistricting matter?Election power is impacted by redistricting. It decides which political party rules the US Congress as well as the state and municipal governments. Redistricting so directly influences which issues a legislature decides to address and which to disregard.Also impacted by redistricting is the representation of the varied populations in the country's legislative bodies. By using redistricting, for instance, one can guarantee that communities of color have an equal opportunity to choose politicians who share their perspective and will support their issues. Another option is to deny them a place at the table. same goes for all other categories of communities of interest.To Learn more About District-based voting Refer To:
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What is the difference between a physical and chemical change ?
Answer:
In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not.
However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.
Hope this helps :)
Recently, I did an experiment on pressure and volume. When I decreased the volume, the pressure decreased, and when I increased the volume, the pressure decreased, like normal. However, when increasing the volume, the pressure recorded was slightly higher than when decreasing the volume. What is the reason for this (I'm sorry for being unable to attach a photo of the results)
Calculate the charge if the energy transferred is 5. 25 kj and the voltage is 15 volts.
The amount of charge given that the energy transferred is 5.25 kilojoules and the voltage is 15 volts will be 0.35 coulombs.
Charge is a property of matter that describes the amount of electrical energy in a substance. It can be positive or negative, and it is measured in units called coulombs. Objects with the same charge will repel each other, while objects with different charges will attract each other. This is the basis of Coulomb's Law and for how electricity works.
The charge, measured in coulombs (C), can be calculated by using the formula:
charge = energy transferred / voltage
charge = 5.25 kJ / 15 V
charge = 0.35 C
Therefore the charge will be 0.35 coulombs.
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two positive charges of 6.0 μc are separated by 0.50m. what force exists between the charges?
The force that exists between the charges is calculated as 1.296 * 10^-18 N.
What is electrostatic force?It is the force of attraction between two opposing charges, protons and electrons.
The electric force between charged bodies at rest is called electrostatic force or Coulomb force. Although the law was known earlier, but it was first published in 1785 by French physicist Charles-Augustin de Coulomb. It is the force of attraction between two opposing charges, protons and electrons.
Given, q1 = q2 = 6 *10^-6
and r = 0.5m
F= 1/4πc * q1 q2/r²
As 1/4πc = 9* 10^-9
= (9* 10^-9 * 6*10^-6*6*10^-6)/0.5²
= 1.296 * 10^-18 J
The force that exists between the charges is 1.296 * 10^-18 N.
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The volume of gas kept at a constant pressure varies inversely with the temperature t. If the temperature is 50 degrees, the volume is 20 cubic feet. What will the volume be when the temperature is 100 degrees?.
The volume of that gas in the 100 degrees temperature will be 100 cubic feet. The condition of the area is isobar or the same pressure. Hence, you have to formulate the solution based on isobars formula.
How to calculate the volume for that condition?As per data given, previous volume (V1) = 20 cubic feet; previous temperature (t1) = 50 degrees; current temperature(t2) = 100 degrees. the condition of the area is in the constant pressure or isobars. The formula we will use in the isobar is V1 : V2 = t1 : t2. So, the calculation would be:
V1 : V2 = t1 : t2
20 : V2 = 20 : 100
20 V2 = 20 x 100
V2 = 100 cubic feet
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A yellow lamp emits light with a wavelength of 6.00 · 10-7 m. How many such photons are required to produce 10.0 joules worth of photons? _____ photons 7.52 x 10 48 3.01 x 10 19 3.01 x 10 49 3.32 x 10 -18
A yellow lamp emits light with a wavelength of 6.00 ·. 3.01 x 10 19 photons such photons are required to produce 10.0 joules worth of photons.
Why are photons immortal?The quanta that make up light are called photons, and in the absence of any other interactions that would cause their characteristics to change, they remain ethereally stable with no indication that they would transform into any other particle.
In addition to releasing energy and generating heat, chemical activities within your body also release small quantities of photons, which are fundamental light particles. The bottom portion of your face and late afternoon are when the glow is most prominent.
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When you eat a healthy snack, what does the process of digesting that snack involve?
Question 9 options:
breaking down food
rejecting insulin
discarding nutrients
movement through the blood
A 0.50 kg mass is attached to a string 1.2 m long and moves in a horizontal circle completing 5 revolution in 1.5 seconds. Calculate:
a) the centripetal acceleration of the mass.
b) the tension in the string.
a) The centripetal acceleration of the mass is 526.38 m/s².
b) The tension in the string is 263.19 N.
What is centripetal acceleration?Centripetal acceleration is a characteristic of an object's motion along a circular path. Centripetal acceleration applies to any item travelling in a circle with an acceleration vector pointing in the direction of the circle's center.
Angular speed of the mass = (5/1.5) revolution per second
= (5 ×2π)/1.5 rad/s
= 20.94 rad/s
a) the centripetal acceleration of the mass = ω²r
= (20.94)²×1.2 m/s²
= 526.38 m/s².
b) the tension in the string = mω²r
= 0.50 kg × 526.38 m/s²
= 263.19 N.
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If a 14.26kg block is sliding down a ramp with a 41 degree incline at 2.361 m/s^2, what is the value of the coefficient of kinetic friction? PART D
The value of the coefficient of kinetic friction is 0.32.
What is the value of coefficient of friction?
The value of the coefficient of friction is calculated by applying Newton's second law of motion as shown below.
Ff = ma
where;
Ff is the force of frictiona is the acceleration of the blockm is the mass of the blockμmg cosθ = ma
μg cosθ = a
μ = a / ( g cosθ )
where;
a is the acceleration of the blockg is acceleration due to gravityθ is the angle of inclination of the blockThe value of the coefficient of kinetic friction is calculated as;
μ = ( 2.361 m/s² ) / ( 9.8 m/s² x cos41 )
μ = 0.32
Thus, the value of the coefficient of kinetic friction between the block and the inclined ramp is a function of the acceleration of the block and the angle of inclination of the ramp.
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8. A penny dropped into a wishing well
reaches the bottom in 1.50 seconds. How
deep was the well?
Answer: 11 meters
Explanation: i'm rlly sorry if i am wrong
An advantage of electromagnets over bar magnets is that you can easily vary the __________ of the magnetic field. What word completes this sentence?.
An advantage of electromagnets over bar magnets is that you can easily vary the strength of the magnetic field.
What is electromagnets?An electromagnet is a type of magnet that is created when an electric current passes through a coil of wire. It produces a magnetic field due to the current flowing through the coil. Electromagnets are used in a wide variety of applications, such as motors, generators, speakers, and magnetic separation equipment. Electromagnets have the advantage of being able to be switched on or off, which allows them to be used in a controlled manner. They are also able to be adjusted in strength, which makes them very versatile and powerful. Electromagnets are also used in magnetic resonance imaging (MRI) machines, where they create a magnetic field that is used to take images of the body's internal structures.
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Question 3 of 5
The gravitational pull of the Moon is much less than the
gravitational pull of Earth.
Which two statements are true for an object with a mass of 20 kilograms that
weighs 44 pounds on Earth?
A. The object's mass would be less on the Moon.
B. The object's mass would be the same on the Moon.
C. The object's weight would be the same on the Moon.
D. The object's weight would be less on the Moon.
Answer:
Number b and c are true
B. The object's mass would be the same on the Moon.
C. The object's weight would be the same on the Moon.
According to Gordon Allport, which type of peronality trait are the mot dominant?
Allport believed that personality of human is categorized into three traits:Cardinal, Central and secondary. Among these traits, there exists a dominant force that defines your personality and influence your behavior, feelings and thoughts. This is called Cardinal Traits.
About Gordon AllportGordon AllportGordon Allport (November 11, 1897 – October 9, 1967) was a psychologist. He earned his doctorate in psychology from Harvard in 1922. He spent his career developing theories, studying social issues, such as prejudice, suspicion, communal, and developing personality tests.
According to Allport, one of the things that most motivates humans is the tendency to fulfill their biological needs. This tendency is called by Allport with opportunistic functioning. Opportunistic functioning is reactive, past oriented, and biological.
Nevertheless, Allport considers this opportunistic functioning is not very important in understanding human behavior, in fact most human behavior is motivated by something else, something that functions in the framework of self-expression, which Allport calls ''Propriate functioning''.
The point is that whatever a person does in life is usually for the sake of showing who he is. This self-function is proactive, future-oriented, and psychological. The word propriate comes from the word proprium which means self-concept. Allport's intention by putting more pressure on the proprium is to define the concept of self as carefully as possible.
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