Answer:Answer is 66.66666666666667
Explanation:all you have to do is divide 200/3
Answer:
66 seconds
Explanation:
time=distance/speed
200/3=66.6
a car travels 200m in 30 s and 400m in the next 90s. Whats the average speed?
Answer:
300m per minute or 5m per second
Acceleration is the rate of change in the speed of an object. To determine the rate of acceleration, you use the formula below. The units for acceleration are meters per second per second or m/s2.
Explanation:
Acceleration is the rate of change in the speed of an object. If initial and final speed are v₁ and v₂. It changes speed in time t. Its formula is given by :
[tex]a=\dfrac{v_2-v_1}{t}[/tex]
The problem is "A skater increases her velocity from 2.0 m/s to 10.0 m/s in 3.0 seconds. What is the skater’s acceleration? "
In this problem,
v₁ = 2 , v₂ = 10 m/s and t = 3 s
Acceleration of the object,
[tex]a=\dfrac{10-2}{3}\\\\a=2.67\ m/s^2[/tex]
So, the acceleration of the skater is [tex]2.67\ m/s^2[/tex].
Muscles covert chemicals energy int
Answer:
Mechanical energy
Explanation:
Mechanical energy is needed for movement of objects. Muscles convert chemical energy provided by the rest of the body to allow movement.
13. A baseball pitcher throws a fastball at a speed of 46m/s. The
acceleration occurs as the pitcher holds the ball in his hand and moves it
through an almost straight line distance of 3.5 m. Calculate the
acceleration, assume it is constant and uniform. (Answer in 3 sig figs and
do not include units) *
Answer: Approximately 302 m/s^2
================================================
Work Shown:
s = starting velocity = 0
f = final velocity = 46
d = distance = 3.5
a = acceleration = unknown (we're solving for this)
[tex]f^2 = s^2 + 2a*d \ \ \text{ ..... one of the kinematics equations}\\\\46^2 = 0^2 + 2a*3.5\\\\2116 = 7a\\\\7a = 2116\\\\a = \frac{2116}{7}\\\\a \approx 302.28571\\\\a \approx 302[/tex]
The acceleration to three sig figs is roughly 302 m/s^2
The acceleration is so large because the ball's final velocity is incredibly fast in such a short amount of time.
If the Mass Number is the sum of the protons and neutrons in an atom, what is
the mass number of
Answer:
It's 31
Explanation:
add 15 and 16
In the desert air, sound travels at 358 meters per second (m/s). In the polar air, sound travels at 330 meters per
second (m/s). What can you conclude from this information?
A - The speed of sound is constant.
B - Sound waves travel fastest in a vacuum.
C-The temperature of the air affects the speed of sound.
D-Sound waves travel at the same speed everywhere on Earth.
Please provide your answer below using CER
1. Claim: What is your choice for the correct answer?
2. Evidence: What evidence did you observe from the test-like question that made you decide on your answer?
3. Reasoning: Provide an elaboration on your evidence, possible prior knowledge about your claim.
Answer:
The correct option is;
C. The temperature of the air affects the speed of sound
Explanation:
The information given are;
The speed with which sound travels in the desert air = 358 m/s
The speed with which sound travels in the polar air = 330 m/s
The major difference between the desert air and the polar air is that the temperature of the desert air is hotter than the temperature of the air in the polar region. Therefore the speed of sound is affected by the air temperature.
The equation that gives the relationship of the speed of sound in air, [tex]v_{air}[/tex], to temperature is presented as follows;
[tex]v_{air} = 331\frac{m}{s} \times \sqrt{\dfrac{T_K}{273 K} } = 331\frac{m}{s} \times \sqrt{1 + \dfrac{T_{^{\circ}C}}{273 ^{\circ} C} }[/tex]
Which shows that the speed of sound in air, [tex]v_{air}[/tex], rises as the temperature of the air rises.
Where;
[tex]T_{^{\circ}C}[/tex] = The temperature of the air in degrees Celsius
[tex]T_K[/tex] = The temperature of the air in degrees Kelvin.
PLEASE HELP
Which object has the least average speed?
A. object A
B. object B
C. object C
D. object D
Answer:
D
Explanation:
I could be wrong, But I'm pretty sure it's D
PLEASE HURRY!
Zach listed the process of how laser beams are produced with crystals.
A flashlamp pumps energy through the crystal.
Atoms in the crystal absorb and then release some of the energy as light.
Light bounces off mirrors and occasionally bounces off crystal atoms, increasing in energy.
Some light escapes the tube through the highly reflective mirror, forming a concentrated beam.
Which best describes Zach’s error?
The crystal pumps energy through the flashlamp; the flashlamp does not pump energy through the crystal.
The atoms in the crystal do not release energy; they only absorb energy.
Light does not bounce off mirrors; it focuses through glass lenses.
Light escapes through the partially reflective mirror, not the highly reflective mirror.
The crystal pumps energy through the flashlamp; the flashlamp does not pump energy through the crystal best describes Zach’s error.
What is a laser?A device that uses stimulated emission of photons from excited atoms or molecules to produce a strong beam of coherent monochromatic light is a laser.
When electrons in optical materials like glass, crystal, or gas absorb energy from an electrical current or light, a laser is formed.
The increased energy excites the electrons, causing them to migrate from a lower-energy orbit around the nucleus to a higher-energy orbit.
The crystal pumps energy through the flashlamp; the flashlamp does not pump energy through the crystal. This statement is incorrect.
Hence Option A best describes Zach’s error.
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Answer:
D. Light escapes through the partially reflective mirror, not the highly reflective mirror.
Explanation:
edge 2022, I took the test.
convert 9.2 km to m
Answer:
9,200 m
Explanation:
1 kilometer = 1000 meters so if there is 9 kilometers then it is 9000 meters, then .2 kilometer is equal to 200 meters. Add the numbers together to get 9,200 meters
The two objects have different masses, the more massive object pulls with a greater force. TRUE OR FALSE?
Answer:
on earth yes, but in space no because there is no gravity
Explanation:
plz can i have some points
The force exerted by an object depends on the mass of the object. Greater mass results in greater force. Hence, the statement is true.
What is force?Force is an external agent acts on a body to change the substance from the state of rest or motion. There are various kinds of force such as nuclear force, magnetic force, frictional force etc.
According to Newton's law of motion force in a moving body is the product of its mass and acceleration. Hence, force is directly proportional to mass and acceleration and an increase in these quantities will increase the force exerted by the body.
Thus, greater force is needed to a move a body with greater mass. If two objects of different masses exerts force each other, the greater force will be exerted by the massive body.
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What force is needed to move a barrel 45-m if 3600 J of work are accomplished?
Answer:
The answer is 80 NExplanation:
The force acting on the object can be found by using the formula
[tex]f = \frac{w}{d} \\ [/tex]
where
d is the distance
w is the work done
We have
[tex]f = \frac{3600}{45} \\ [/tex]
We have the final answer as
80 NHope this helps you
An object is moving back and forth on the x-axis according to the equation x(t) = 3sin(20πt), t> 0, where x(t) is measured in cm and t in seconds. Give decimal answers below. (a) How many complete back-and-forth motions (from the origin to the right, back to the origin, to the left and finally back to the origin) does the object make in one second? (b) What is t the first time that the object is at its farthest right? (c) At the time found in part (b), what is the object's velocity? (d) At the time found in part (b), what is the object's acceleration?
Answer:
a.) 10Hz
b.) 0.1 s
c.) 187.4 m/s
d.) -412.6 m/s^2
Explanation:
Given that an object is moving back and forth on the x-axis according to the equation x(t) = 3sin(20πt), t> 0, where x(t) is measured in cm and t in seconds. Give decimal answers below.
(a) How many complete back-and-forth motions (from the origin to the right, back to the origin, to the left and finally back to the origin) does the object make in one second?
from the equation given, the angular speed w = 20π
but w = 2πf
where f = frequency.
substitute w for 20π
20π = 2πf
f = 20π/2π
f = 10 Hz
(b) What is t the first time that the object is at its farthest right?
since F = 1/T
T = 1 / f
T = 1/10
T = 0.1 s
Therefore, the t of first time that the object is at its farthest right is 0.1 s
(c) At the time found in part (b), what is the object's velocity?
The velocity can be found by differentiating the equation;
x(t) = 3sin(20πt)
dx/dt = 60πcos(20πt)
where dx/dt = velocity V
V = 60πcos(20π * 0.1)
V = 187.4 m/s
(d) At the time found in part (b), what is the object's acceleration?
to get the acceleration, differentiate equation V = 60πcos(20πt)
dv/dt = -1200πSin(20πt)
dv/dt = acceleration a
a = -1200πSin(20πt)
substitute t into the equation
a = -1200πSin(20π * 0.1)
a = - 412.6 m/s^2
The type of motion the object undergoes that consist of a back-and-forth
movement that is repetitive is a simple harmonic motion.
The correct responses are;
(a) Number of complete back-and-forth motions per second is 10(b) The first time is after 0.025 seconds(c) Velocity is 0(d) Acceleration is approximately -11843.53 m/s²Reasons:
The equation that represents the motion of the object is x(t) = 3·sin(20·π·t)
Where;
t ≥ 0
x(t) is in cm, and t is in seconds.
(a) The general sine function is y = A·sin(B·(t - C) + D
[tex]\mathrm{The \ period \ P} = \dfrac{2 \cdot \pi}{B}[/tex]
By comparison, we have;
B = 20·π
Therefore;
[tex]P = \dfrac{2 \cdot \pi}{20 \cdot \pi} = \dfrac{1}{10} = 0.1[/tex]
The period, which is the time to complete one cycle = 0.1 seconds
The number of cycle completed per second, is the frequency, f
[tex]f = \dfrac{1}{P} = \dfrac{1}{0.1} = 10[/tex]
f = 10 Hz = 10 cycles
The number of cycle completed per second is f = 10 cycles
(b) When the object is at the farthest right, we have;
sin(20·π·t) = Maximum = 1
[tex]\mathbf{sin\left(\dfrac{\pi}{2}\right)} = 1[/tex]
Therefore,
[tex]20 \cdot \pi \cdot t = \dfrac{\pi}{2}[/tex]
[tex]t = \dfrac{\pi}{20 \cdot \pi \cdot 2} = \dfrac{1}{40} = 0.025[/tex]
The first time it is at the farthest right is t = 0.025 seconds after start
(c) [tex]\mathrm{Velocity, \ v, \ is \ given \ by \ v = \dfrac{dx(t)}{dt}}[/tex]
Therefore;
[tex]v = \dfrac{dx(t)}{dt} = \dfrac{dx(t)}{dt} \left(3 \cdot sin \left(20 \cdot \pi \cdot t \right) = 60\cdot \pi \cdot cos \left(20 \cdot \pi \cdot t \right)[/tex]
At t = 0.25 seconds, we have;
[tex]v = \dfrac{dx(t)}{dt} = 60\cdot \pi \cdot cos \left(20 \times \pi \times 0.025 \right) = 0[/tex]
The velocity of the object at the t = 0.025 seconds is v(t) = 0
(d) Acceleration, a, is given by [tex]a = \dfrac{dv(t)}{dt}[/tex]
Therefore;
[tex]a = \dfrac{dv(t)}{dt} = \dfrac{d}{dt} \left( 60\cdot \pi \cdot cos \left(20 \times \pi \times t\right) \right) =-1200 \cdot \pi ^2 \cdot sin(20 \cdot t \cdot \pi)[/tex]
a = -1200·π²·sin(20·t·π)
∴ a = -1200×π²×sin(20×0.025×π)
sin(20×0.025×π) = 1
∴ a = -1200×π²×1 ≈ -11843.53
At the time found in part b the acceleration of the object, a ≈ -11843.53 m/s²
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To decorate for a party, Simon needs 1,850 centimeters of colorful streamers. If the ratio of meters to centimeters is 1 : 100, how many meters of streamers does he require?
A.
18,500 meters
B.
185 meters
C.
18.5 meters
D.
1.85 meters
Describe effect of artificial selection on the process of evolution
Answer: The process is called artificial selection because people (instead of nature) select which organisms get to reproduce.
Explanation: This is evolution through artificial selection and the characteristics to reproduce, causing the evolution of farm stock.
The MSDS for chloroform indicates that it is a clear liquid that has a pleasant smell and substantial vapor pressure. People should avoid inhaling its vapors, and it is sensitive to light. Malik needs 10 mls of chloroform for an experiment.
According to this information, how should he safely pour the chloroform?
He should locate the chloroform stored in a transparent container in chemical storage and pour directly into his beaker from that location.
He should locate the chloroform stored in a transparent container in chemical storage and should take it to the fume hood to pour.
He should locate the chloroform stored in a dark container in chemical storage and should take it to the fume hood to pour.
He should locate the chloroform stored in a dark container in chemical storage and pour directly into his beaker from that location.
Answer:
The correct option is the third option
Explanation:
Firstly, it must be noted that chemicals/reagents that are sensitive to sunlight are stored in dark/amber container in the laboratory. Hence, the chloroform can only be found in an amber/dark bottle.
Also, reagents/chemicals that release poisonous/offensive gases are handled in the fume cupboard in the laboratory. Thus, If Malik is going to pour the chloroform, he should pour it in a fume cupboard to avoid inhaling it because of the toxicity of it's vapor.
From the above explanation, it can be deduced that Malik should locate the chloroform stored in a dark container in chemical storage and should take it to the fume hood to pour.
Answer:
He should locate the chloroform stored in a dark container in chemical storage and should take it to the fume hood to pour.
Explanation:
A car moved 40 km north and 90 km south. What is the displacement of the car?
A. 50 km south
B. 50 km north
C. 10 km east
Answer:
A. 50 km south
Explanation:
hope this helps!
When a light ray enters water, its velocity is _________.
Answer:
UR ANSWER IS WAVELENGTH
How many significant figures? 53,598 m/sec
Answer:
This has 5 significant figures.
MathPhys Pls PLS PLS PLS HELP ME!!!!
Which of these statements describes the relationship between mass and weight?
(1 Point)
Mass is always greater than weight.
Mass of an object changes based on location, weight stays constant.
Mass of an object is constant, weight changes based on location.
Mass and weight are the same measurement.
Answer:
Usually, the relationship between mass and weight on Earth is highly proportional; objects that are a hundred times more massive than a one-liter bottle of soda almost always weigh a hundred times more—approximately 1,000 newtons, which is the weight one would expect on Earth from an object with a mass slightly greater ...
If a bicyclist travels at 15 km/h, how long will it take her to travel 30 km?
A runner is jogging in a straight line at a steady vr= 7.3 km/hr. When the runner is L= 2.1 km from the finish line, a bird begins flying straight from the runner to the finish line at vb= 29.2 km/hr (4 times as fast as the runner). When the bird reaches the finish line, it turns around and flies directly back to the runner After this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. The bird repeats the back and forth trips until the runner reaches the finish line. How far does the bird travel from the beginning (including the distance traveled to the first encounter
Answer:
Explanation:
Time taken by jogger to travel the distance to finishing line = 2.1 / 7.3
= .28767 hr
Bird will keep flying for this time period
distance covered by bird = speed x time
= 29.2 x .28767 km
= 8.4 km .
If two cars are 5 m apart, and one car has a mass of 2,565 kg and the other
car has a mass of 4,264 kg, what is the gravitational force between the two
cars? Newton's law of gravitation is F gravity
Gm; m2 The gravitational
constant G is 6.67 x 10-11 Nm2/kg?.
A. 5.84 x 10-6N
B. 4.37 % 105 N.
C. 1.46 10-4N
D. 2.92 x 10-5 N
Gravitational force between two cars are 2.92 × 10 ⁻¹¹ Nm²/kg.
The universal force of attraction happened between two objects is called as gravitational force.
The mass of the two cars, m₁ = 2565 kg
m₂ = 4264 kg
r = 5m
G = 6.67 ₓ 10 ⁻11 Nm²/kg
How gravitational force can be calculated?
Definition of gravitational force: The force of attraction between any two bodies is directly proportional to the product of the masses and inversely proportional to the square of the distance between them.
F ∝ m₁ m₂ ÷ r²
where the force exerted between the two masses m₁ and m₂,
F = G (m₁ m₂) ÷ r²
where as, F - Gravitational force between two bodies,
G - Gravitational constant,
m₁ - mass of the first body,
m₂ - mass of the second body,
r² - square of the distance between two bodies.
F= 6.67 × 10⁻¹¹ Nm²/kg ( 2565 kg × 4264 kg) ÷ ( 5²)
Hence,
F = 2.92 × 10⁻⁵ N
Option D is correct answer.
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If the bands in an igneous rock are dark. What kind of magma was present when it was formed?
Answer:
The magma, molten rock under the surface, and lava (molten rock on the surface) harden into igneous rock. The igneous rock then breaks apart over time through the process of weathering.
Explanation:
How long will it take a car to go from a complete stop to 44 km/hr if they are accelerating at 5 km/hr^2
Answer:
8.8 hours
Explanation:
plz give me a Brainliest
Explain and reason why the the moon rotates around the earth every lunar cycle
Pls explain ASAP
Best answer will be marked as BRAINLIEST✨
You use a knife to cut a piece of bread. What kind of simple machine are you
using?
A. Wedge
B. Inclined plane
C. Screw
O D. Lever
Answer:
the answer is A.) Wedge
A knife to cut a piece of bread is a A. Wedge
What is a simple machine?
A simple machine, any of several devices with few or no moving parts that are used to modify motion and the magnitude of a force in order to perform work.
since , a wedge is a simple machine with two inclined planes which when put together forms a sharped edge, which forms a triangular shaped tool which can be used to separate portion of two objects .
hence , a knife to cut a piece of bread is a A. Wedge
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a train starting from a distance of velocity of 90 km.h
-1 in 10 minutes assuming that the acceleration is uniform find the acceleration and the distance travelled by the train for attending the velocity
To make this problem solvable and you can get the help you need, I'll complete and arrange some data.
Answer:
Acceleration: [tex]0.0417\ m/s^2[/tex], Distance=7,500 m
Explanation:
Uniform Acceleration Motion
It's a type of motion in which the velocity of an object changes uniformly over time.
Being a the constant acceleration, vo the initial speed, vf the final speed, and t the time, the following relation applies:
[tex]v_f=v_o+at\qquad\qquad [1][/tex]
The distance traveled by the object is given by:
[tex]\displaystyle x=v_o.t+\frac{a.t^2}{2}\qquad\qquad [2][/tex]
Using the equation [1] we can solve for a:
[tex]\displaystyle a=\frac{v_f-v_o}{t}\qquad\qquad [3][/tex]
The problem will be rewritten as follows:
A train starting from rest reaches a velocity of 90 km/h in 10 minutes. Assuming that the acceleration is uniform, find the acceleration and the distance traveled by the train for attending the velocity.
Let's take the relevant data:
vo=0
vf=90 Km/h*1000/3600 = 25 m/s
t = 10 minutes = 10*60 = 600 seconds
Now compute the acceleration by using [3]:
[tex]\displaystyle a=\frac{25-0}{600}=0.0417[/tex]
[tex]a=0.0417\ m/s^2[/tex]
Finally, compute the distance:
[tex]\displaystyle x=0*600+\frac{0.0417\cdot 600^2}{2}[/tex]
[tex]x=7,500\ m[/tex]
Note: We used the value of the acceleration with more precision than shown.
Acceleration: [tex]\mathbf{0.0417\ m/s^2}[/tex], Distance=7,500 m
The level of toluene (a flammable hydrocarbon) in a storage tank may fluctuate between 10 and 400 cm from the top of the tank. since it is impossible to see inside the tank, an open-end manometer with water or mercury as the manometer fluid is to be used to determine the toluene level. one leg of the manometer is attached to the tank 500 cm from the top. a nitrogen blanket at atmospheric pressure is maintained over the tank contents. felder, richard m.; rousseau, ronald w.; bullard, lisa g.. elementary principles of chemical processes, 4th edition (page 81). wiley. kindle edition.
Complete Question
The complete question is shown on the first and second uploaded image
Answer:
When water is used the reading is [tex] R = 2281.6 \ cm [/tex]
When mercury is used the reading is [tex] R = 23.83 \ cm [/tex]
The best fluid to use is mercury because for water a slight change in toluene level will cause a large change in height .
Explanation:
From the question we are told that
The length of the leg of the manometer to the top of the tank is d = 500cm
The toluene level where in the tank where the height of the manometer fluid level in the open arm is equal to the height where the manometer is connected to the tank is h =150 cm
The manometer reading is R
Generally at the point where the height of the open arm is equal to the height of the of the point connected to the tank ,
The pressure at the height of the both arms of the manometer corresponding to the base of the tank are equal
i.e [tex]P_1 = P_2[/tex]
Here [tex]P_1[/tex] is the pressure of the manometer at the point corresponding to the base of the tank and this is mathematically represented as
[tex] P_{atm} + P_1 = P_{atm} + P_t[/tex]
Here [tex]P_t[/tex] is the pressure due to the toluene level in the tank and in the arm of the manometer connected to the tank and this is mathematically represented as
[tex]P_t = \rho_t * g * h_i[/tex]
Here
[tex]\rho_t [/tex] is the density of toluene with value [tex]\rho_t = 867 kg/m^3 [/tex]
[tex]h_i[/tex] is the height of the connected arm above the point equivalent to the base of the tank , this mathematically represented as
[tex]h_i = d - h + R[/tex]
and [tex] P_2 [/tex] is the the pressure at the open arm of the manometer at the point equivalent to the base of the base of the tank and this is mathematically represented as
[tex] P_2 = \rho_f * g * h_f [/tex]
Here
[tex]\rho_f[/tex] is the density of the fluid in use , if it is water the density is
[tex]\rho_w = 1000 \ kg /m^3 [/tex]
and if it is mercury the density is
[tex]\rho_m = 13600 \ kg /m^3 [/tex]
[tex]h_f[/tex] is the height of the fluid in the open arm of the manometer from the point equivalent to the base of the tank which is equivalent the manometer reading R
So when the fluid is water we have
[tex] P_{atm} + \rho_t* g *(d - h + R) = P_{atm} + \rho_f * g * h_f[/tex]
=> [tex] \rho_t* (d - h + R) = \rho_w * h_f[/tex]
=> [tex] 867 (500 - 150 + R) = 1000 * R [/tex]
=> [tex] R = 2281.6 \ cm [/tex]
So when the fluid is mercury we have
[tex] \rho_t* (d - h + R) = \rho_m * h_f[/tex]
=> [tex] 867 (500 - 150 + R) = 13600 * R [/tex]
=> [tex] R = 23.83 \ cm [/tex]
The difference in the mercury reading for mercury due to the fact that they have different densities as we have seen in this calculation
So the best fluid to use is mercury because for water a slight change in toluene level will cause a large change in height .
The data table shows how the amplitude of a mechanical wave varies with
the energy it carries. Analyze the data to identify the mathematical
relationship between amplitude and energy. Use your equation to find the
energy if the amplitude is 6 units.
Amplitude
Energy
1 unit
2 units
2 units
8 units
3 units
18 units
4 units
32 units
Answer:
162
Explanation:
When the amplitude of the wave is 8 units, the corresponding energy of the wave is 128 units. Therefore, option C is correct.
What do you mean by an amplitude ?The term amplitude is defined as the maximum distance moved by a point on a vibrating body or wave calculated from its equilibrium position.
We have given,
first amplitude, A = 1, corresponding energy = 2
second amplitude, A = 2, corresponding energy = 8
The energy of a string at a given amplitude is calculated as follows;
E ∝ A²
Energy varies as the square of the change in amplitude.
If amplitude of one has energy of two
Amplitude of 2 (double of 1)
= ( 2 x 2 ) = 4 x 2
= 8 4 times the energy at amplitude of 1.
Then for 8 units of amplitude change
8 x 8 = 64 x 2
= 128
Thus, When the amplitude of the wave is 8 units, the corresponding energy of the wave is 128 units, option C is correct.
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Your question is incomplete, most probably your question was
The data table shows how the amplitude of a mechanical wave varies with the energy it carries. Analyze the data to identify the mathematical relationship between amplitude and energy. Use your equation to find the energy if the amplitude is 8 units.
Amplitude
1
2
3
4
energy
2
8
18
32
A.66 units
B. 108 units
C. 128 units
D. 88 units
What is better for measuring how hard you are actually working, Target Heart Rate or Rating of perceived exertion?
Answer:
Rating of percieved exertion