Answer:
Spurious relationship
Explanation:
In statistics a spurious relationship is a correlated mathematical relationship of covariation between two variables or more which by themselves have no cause and effect relationship as a result of a coincidence or the existence of a third or confounding factor
The variables have covariation due to their correlation but they don't have a cause and effect relationship
An example of a spurious relationship is the increase in ice cream sales when there is an observed increase in the rate of drowning.
Help me please, it's so hard
Answer:
4.58×10²³ atoms
5.94×10⁻²¹ J
1340 m/s
Explanation:
Use ideal gas law to find moles of gas.
PV = nRT
(1.266 atm × 101300 Pa/atm) (4/3 π (0.15 m)³) = n (8.31451 J/mol/K) (14 + 273) K
n = 0.760 mol
Use Avogadro's number to find number of atoms.
(0.760 mol) (6.02214×10²³ atom/mol) = 4.58×10²³ atoms
Average kinetic energy per molecule is:
KE = 3/2 kT
KE = 3/2 (1.38066×10⁻²³ J/K) (14 + 273) K
KE = 5.94×10⁻²¹ J
RMS speed of each atom is:
KE = 1/2 mv²
5.94×10⁻²¹ J/atom = 1/2 (0.004 kg/mol) (1 mol / 6.02214×10²³ atom) v²
v = 1340 m/s
The moon’s rotational period and revolution period are equal. What is the result of this? Enter your answer in the space provided.
Answer The Moon has synchronous rotation: it's rotation period is the same as its period of revolution
Explanation:
The Moon has synchronous rotation: it's rotation period is the same as its period of revolution
What is the missing number in the nuclear reaction shown below?
+
233
92
4
2
He +
?
90
Th
Answer here
SUBMIT
Answer:
[tex]\boxed{299}[/tex]
Explanation:
In this reaction, Sum of Atomic Masses of Left side = Sum of Atomic Masses of right side
Let the atomic mass of Thorium be x
So,
233 = 4 + x
Subtracting 4 to both sides
x = 233-4
x = 229
a ball is projected with a certain angle with initial velocity u. it covers horizontal range R. With what initial velocity it must be projected keeping the angle of projection same so its horizontal range becomes 2.25R
Answer:
1.5 u
Explanation:
The range equation is:
R = u² sin(2θ) / g
When u = v, R = 2.25 R.
2.25 R = v² sin(2θ) / g
2.25 u² sin(2θ) / g = v² sin(2θ) / g
2.25 u² = v²
1.5 u = v
Molecules on an acid-base indicator react chemically with lons in a solution, causing the indicator to change color. Which ions in the solution cause this reaction?
Explanation:
the colour change of PH indicator is caused by the dissociation of the H+ ion from the indicator itself recall the pH indicator are not only natural dyes but also a weak acid the dissociation of weak and Indicator causes a solution to change color
explain what a insulator , conductor, and semi conductor is and what it does
Conductors are the substance that transmits heat or electricity through them, insulators are basically the opposite. They prevent heat or electricity from passing through them. Semiconductors can act as either a conductor or an insulator under different conditions.
help please, I need it
Answer:
1.97×10⁻²¹ J
Explanation:
Use ideal gas law to find temperature.
PV = nRT
(9 atm) (9 L) = (83.3 mol) (0.0821 L·atm/mol/K) T
T = 11.9 K
The average kinetic energy per atom is:
KE = 3/2 kT
KE = 3/2 (1.38×10⁻²³ J/K) (11.9 K)
KE = 2.46×10⁻²² J
For a mass of 5.34×10⁻²⁶ kg, the kinetic energy is:
KE = (5.34×10⁻²⁶ kg) (1 mol / 0.004 kg) (6.02×10²³ atom/mol) (2.46×10⁻²² J)
KE = 1.97×10⁻²¹ J
Write a report on the lap experiment: Motion with Constant Acceleration
Answer:
Purpose: To observe how an object’s position and velocity change while it is moving with a constant acceleration.
Question: How does an object’s position and velocity change as the object accelerates?
Hypothesis: If the fan speed increases, then the acceleration of the cart increases, because a greater fan speed supplies more energy to move the cart.
Variables:
• Independent variable: fan speed
• Dependent variable: acceleration of the cart
• Controlled variables: mass
Materials:
• Cart with Fan (1 kg)
• CM ruler (1 cm)
• Stop watch (0.0 cm pe sec)
• Flag
Procedure:
1. Use the setup on “Force and Fan Carts” Gizmo.
2. First, put the fan speed on low and no friction surface.
3. Press the start button and record the final time when the cart crosses the finished line. Record on table B.
4. Then, click on the data tab to record the speed data, total distance, average velocity, and acceleration. Record on table A and B.
5. After, observe the position vs. time graph with the speed and line graph toggled. Record on table C.
6. Repeat steps 2-5 on fan speed on medium and high with no friction surface.
7. Next, reset and put fan speed on low.
8. Press start and pause on 4 seconds.
9. On the same trial turn off the fan speed and hit start again.
10. Observe the graph and write observations on table D.
Analysis and Conclusion:
In conclusion, my hypothesis matches the data, because the data shows that increasing the fan speed increases the acceleration of the cart. The trends for all fan speeds are linear slope for speed. The higher the fan speed, the less time it took for the cart to cross the finish line.
Data:
Explanation:
Sorry can’t copy and paste results
Answer:
for that pervious answer why cant we copy and paste?
Explanation:
Help me please savior
Answer:
-16°C
Explanation:
PV = nRT
V and n are constant.
P / T = P / T
(2 atm + 1 atm) / (266 K) = (1.9 atm + 1 atm) / T
T = 257.1 K
T = -16°C
What does it mean for a system to be in dynamic equilibrium? (2 points)
Select one:
a. The rate of the forward reaction equals the rate of the backward reaction.
b. The concentration of products decreases.
c. The overall rate of the reaction slows down.
d. The temperature of the system is stable.
Answer:
A
Explanation:
A dynamic equilibrium is a chemical equilibrium between a forward reaction and the reverse reaction where the rate of the reactions are equal.
The rate of the forward reaction equals the rate of the backward reaction.
For a system to be in dynamic equilibrium, the forces should be balanced.
What is dynamic equilibrium?According to chemistry, Dynamic equilibrium is all about the equal rate of change in reactants and products, i.e., there will be a steady state. Also in Physics, if though the number of the composition of mixtures happens and that does not change with time, i.e., it is equilibrium constant. For example, when the car moving on the road, there will be some friction. The forward force of the car happened due to friction but no other force has changed at car's constant speed. When the net force will be same then it is known to be dynamic equilibrium.
Equilibrium constants can be determined as rate constants through reversible reaction, i.e., the rate of the forward reaction equals to the rate of the backward reaction.
Thus, option A is correct.
Learn more about dynamic equilibrium
https://brainly.com/question/26034510
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What is the mathematical equation for calculating the internal energy of a
diatomic gas?
-
Answer:
U = 5/2 NkT.
Explanation:
A diatomic molecule = H₂, O₂, N₂ .....etc
A diatomic molecule has 5 degrees of freedom.
3 transnational modes = x, y, z2 rotational modes = ωx , ωySo, the internal energy for diatomic gases is :
U = 5/2 NkT.
And observer reviews for identical objects that are traveling at speed close to the speed of light in their legs be used to rank the objects according to their speeds A. No the Lankes of the four objects should be the same regardless of the speed B. Yes the shortest object is traveling the fastest C. Yes the longest object is traveling the fastest D. No the length of each object demands on the frame of reference of the observer
Answer:
C :)
Explanation:
Peter, a 100 kg basketball player, lands on his feet after completing a slam dunk and then immediately jump up again to celebrate his basket. When his feet first touch the floor after the dunk,
his velocity is 5 m/s downward; when his feet leave the floor 0.50 s later, as he jumps back up,
his velocity is 4 m/s upward. What is the average reaction force exerted upward by the floor on Peter during this 0.50 s?
Answer:
1800 N
Solution:
Impulse = mΔv = m * (u - v) .
here m = 100 kg
u = 4 m/s
v = -5 m/s
impulse = 100 x ( 4 - ( -5 ) ) = 900 Kg m/s .
Average reaction Force ( Favg ) = impulse / Δt
Average reaction Force ( Favg ) = 900kg·m/s / 0.5s
Average reaction Force ( Favg ) = 1800 N
conditions of equilibrium of parallel coplanar forces
Answer:
Bruh............
Explanation:
If 400 joules of heat are added to a gas in an isochoric process, what is the
change in its internal energy?
O A. 400 J
O B.-400 J
O C. 100 J
OD. 200
Answer:
A. 400 J
Explanation:
Because the process is isochoric, no volume change, so no work, so none of the energy is lost or converted. In other words, the system will gain and hold onto all of the J of heat put into it, which was 400J
Which statement is accurate about mass or weight? A. Mass can be measured in newtons. B. Weight can be measured in pounds. C. A bowling ball has the same mass as a golf ball. D. Objects have the same weight regardless of where they are.
Answer:
Option B
Explanation:
Weight can be measured in pounds. Pounds is a unit of weight.
=> Mass is measured in kgs
=> A bowling ball has more mass than a golf ball.
=> Objects do not have the same weight regardless of where they are. The weight depends on where they are as it depends on the acceleration due to gravity (g)
Answer:
B
Explanation:
What is Radioactivity? ;-;
Answer:
the emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.
Explanation:
HOPE I HELPED
PLS MARK BRAINLIEST
DESPERATELY TRYING TO LEVEL UP
✌ -ZYLYNN JADE ARDENNE
Answer:
is the process by which an unstable atomic nucleus loses energy by radiation
Explanation:
hope this helps
halp please mate help
Answer:
( a ) : Pool B
( b ) The final equilibrium temperature will be about 38°C
Explanation:
Attachment 1 : The second pool ( pool B ) had more heat transferred to it, as you can see that it's temperature rose 10 degrees Celcius comparative to pool A, that rose by 9 degrees Celcius. Though the temperature difference is minumum, pool B did have more heat transferred to it.
Attachment 2 : So as we can see, the specific heat of iron and water is given by the units J / kg [tex]*[/tex] C. The mass of each substance is also given by kilograms, so there is no need for conversions here. The heat gained by each substance is equivalent to each other, so to determine the final temperature, consider the change in temperature in the formula q = m [tex]*[/tex] c [tex]*[/tex] Δ T.
For the iron horseshoe, the change in temperature will be as such : Δ T = [tex]T_f[/tex] - 693, where [tex]T_f[/tex] = Final Temperature. Respectively the change in temperature for the water will be Δ T = [tex]T_f[/tex] - 39, where [tex]T_f[/tex] = Final Temperature. Using this information let us solve for [tex]T_f[/tex].
q = m [tex]*[/tex] c [tex]*[/tex] Δ T - where q = heat gained, m = mass of substance, c = specific heat of substance
Δ T = [tex]T_f[/tex] - 693 and Δ T = [tex]T_f[/tex] - 39,
[tex]( 0.33 )( 448 )( T_f - 693 ) = ( 24 )( 4186 )( T_f - 39 )[/tex] - let's say [tex]T_f[/tex] = x,
[tex]\left(0.33\right)\left(448\right)\left(x-693\right)=\left(24\right)\left(4186\right)\left(x-39\right)[/tex],
[tex]147.84x-102453.12=100464x-3918096[/tex],
[tex]147.84x=100464x-3815642.88[/tex],
[tex]-100316.16x=-3815642.88[/tex],
[tex]\frac{-100316.16x}{-100316.16}=\frac{-3815642.88}{-100316.16}[/tex],
[tex]x=38.03617\dots[/tex]
The final equilibrium temperature will be about 38°C.
A skydiver has a mass of 110 kg. At what speed will she have a momentum
of 1000 kg•m/s?
O A. 2.1 m/s
B. 9.1 m/s
C. 28.6 m/s
D. 14.3 m/s
Answer:
[tex]\boxed{B}[/tex]
Explanation:
[tex]v=\frac{p}{m}[/tex]
[tex]v=velocity\\p=momentum\\m=mass[/tex]
[tex]v=?\\p=1000\\m=110[/tex]
[tex]v=\frac{1000}{110}[/tex]
[tex]v \approx 9.09[/tex]
What will be the pressure exerted by the object if 5000N of the force is acting on an area of 200 cm square
You are in a desert on a hot day and see water in the distance. It is not really there, you see it because light bends due to a difference in the temperature of air. Which behavior of light best explains this? Select one: a. reflection b. translocation c. diffraction d. refraction
Answer:
d) refraction
Explanation:
in physics, refraction is the change of direction of a wave passing from one medium to another. refraction of light is the most commonly observed phenomenon but other waves such as sound waves and water waves also experience refraction
Answer:
B. Translocation
Explanation:
It means a change in location. It often refers to genetics, when part of a chromosome is transferred to another chromosome, you want a change in location because you are so thirsty in the desert and need water
Help me please, please !
Answer:
b and d
a, c, e, and f
Explanation:
Ideal gas law:
PV = nRT
Solving for temperature:
T = PV / (nR)
Therefore, temperature is directly proportional to pressure and volume, and inversely proportional to the number of molecules.
T = k PV / N
Let's say that T₀ is the temperature when P = 100 kPa, V = 4 L, and N = 6×10²³.
a) T = k PV / N = T₀
b) T = k (2P) V / N = 2T₀
c) T = k (P/2) (2V) / N = T₀
d) T = k PV / (N/2) = 2T₀
e) T = k P (V/2) / (N/2) = T₀
f) T = k (P/2) V / (N/2) = T₀
b and d have the highest temperature,
a, c, e, and f have the lowest temperature.
Help me please, ;) I could use it
Answer:
The solution(s) are in order with respect to the attachments
[tex]2.613\:\cdot10^5[/tex] Joules ; 5. Adding the same amount of heat to two different objects will produce the same increase in temperature ; 2. Same speed in both ; 2. A
Explanation:
Diagram 1 ( Liquid Nitrogen ) : So as you can see, we want our units in Joules here, and can therefore multiply the mass of gaseous nitrogen and the latent heat of liquid nitrogen, to cancel the units kg, and receive our solution - in terms of Joules. Let's do it.
q ( energy removed ) = mass of nitrogen [tex]*[/tex] latent heat of liquid nitrogen,
q = 1.3 kg [tex]*[/tex] 2.01 [tex]*[/tex] 10⁵ J / kg = [tex]1.3\:\cdot \:2.01\:\cdot \:\:10^5[/tex] = [tex]10^5\cdot \:2.613[/tex] = [tex]100000\cdot \:2.613[/tex] = [tex]261300[/tex] Joules = [tex]261.3[/tex] kiloJoules = 2.613 [tex]*[/tex] 10⁵Joules is the energy that must be removed
Diagram 2 : The same amount of heat does not necessarily mean the same increase in temperature for two different objects. The increase in temperature depends on the specific heat capacity of the substance. Therefore your solution is 5 ) Adding the same amount of heat to two different objects will produce the same increase in temperature.
Diagram 3 : The temperatures in both glasses are the same, and hence the molecules have the same average speed. Therefore your solution is 2 ) Same speed in both.
Diagram 4 : Glass A has more water molecules, and hence has more thermal energy. Your solution is 2 ) A.
1. If an object that stands 3 centimeters high is placed 12 centimeters in front of a plane
mirror, how far from the mirror is the image located? Explain your reasoning.
2. An object with a height of 0.3 meter is placed at a distance of 0.4 meter from a concave
spherical mirror. An image with a height of 0.1 meter is formed in front of the mirror.
How far from the mirror is the image located?
3. When an object with a height of 0.10 meter is placed at a distance of 0.20 meter from a
convex spherical mirror, the image will appear to be 0.06 meter behind the mirror.
What's the height of the image?
4. Compare and contrast the properties of the images formed by each mirror type in the
table.
Answer:
1. 12 cm
2. 0.133 m
3. 0.03 m
4. Plane mirror
Virtual image
Upright
Behind the mirror
The same size as the object
Concave mirror when the object is located a distance greater than the focal length from the mirror's surface
Real image
Inverted image
In front of the the mirror
Diminished when the object is beyond the center of curvature
Same size as object when the object is placed at the center of curvature
Enlarged when the object is placed between the center of curvature of the mirror and the focus of the mirror
Concave mirror when the object is located a distance less than the focal length from the mirror's surface
Virtual image
Upright image
Behind the the mirror
Enlarged
Convex mirror
Type = Virtual image
Appearance = Upright image
Placement = Behind the mirror
Size = Smaller than the object
Explanation:
1. For plane mirror, since there is no magnification, the virtual image distance from the mirror = object distance from the mirror = 12 cm behind the mirror
2. The height of the object = 0.3 m
The distance of the object from the mirror = 0.4 meters
Height of image formed = 0.1 meter
We have;
[tex]Magnification, \ m = \dfrac{Image \ height }{Object \ height } = \dfrac{Image \ distance \ from \ mirror }{Object\ distance \ from \ mirror }[/tex]
[tex]m = \dfrac{0.1}{0.3 } = \dfrac{Image \ distance \ from \ mirror }{0.4 }[/tex]
Image distance from the mirror = 0.1/0.3×0.4 = 2/15 = 0.133 m
Image distance from the mirror = 0.133 m
3. [tex]m = \dfrac{Image \ height}{0.10 } = \dfrac{0.06 }{0.20 }[/tex]
The image height = 0.06/0.2×0.1 = 3/100 = 0.03 meter
The image height = 0.03 meter
4. Plane mirror
Type = Virtual image
Appearance = Upright image with the left transformed to right
Placement = Behind the mirror
Size = The same size as the object
Concave mirror when the object is located a distance greater than the focal length from the mirror's surface
Type = Real image
Appearance = Inverted image
Placement = In front of the the mirror
Size = Diminished when the object is beyond the center of curvature
Same size as object when the object is placed at the center of curvature
Enlarged when the object is placed between the center of curvature of the mirror and the focus of the mirror
Concave mirror when the object is located a distance less than the focal length from the mirror's surface
Type = Virtual image
Appearance = Upright image
Placement = Behind the the mirror
Size = Enlarged
Convex mirror
Type = Virtual image
Appearance = Upright image
Placement = Behind the mirror
Size = Smaller than the object.
Answer:
1. The mirror is 12 centimeters away from the image. This is a plane mirror with a flat reflecting surface. The distance between the object and the mirror surface is equal to the distance between the mirror surface and the image.
2. hiho=siso
0.1 m0.3 m=si0.4 m
Multiply each side of this equation by 0.4.
0.4×(0.10.3=si0.4)×0.4
si=0.40.3
si = 0.133 m
3. hiho=siso
hi0.10 m=0.06 m0.02 m
Multiply each side of this equation by 0.10.
0.10×(hi0.10=0.060.20)×0.10
hi=0.0060.20
hi = 0.03 m
4.
Image Formation
Mirror Type Appearance Placement Size
Plane Virtual Erect (Upright); Appears to have left and right reversed Behind the mirror; the distance between the mirror and the image is equal to the distance between the mirror and the object Depends on the size of the mirror and placement of the object
Concave (when the object is located a distance greater than a focal length from mirror's surface) Real Inverted In front of the mirror Smaller than the object
Concave (when object is located a distance less than the focal length of the mirror) Virtual Erect (Upright) Behind the mirror Enlarged
Convex Virtual Erect (Upright) Behind the mirror Smaller than the object
Explanation:
PENN
A -0.00125 C charge is placed 3.62 m from a +0.00333 C charge. What is the magnitude of the electric force between them?
Remember, magnitudes are positive.
[?] N
Answer: 2858.7726N
Explanation:
Given that :
Charge 1 (q1) = -0.00125 C
Charge 2 (q2) = +0.00333 C
Distance (r) = 3.62 m
According to columb's Law: The magnitude of the force between any two charged objects :
Fe = (Kq1q2) / r^2
Coloumb's constant(k) = 9×10^9 Nm^2/C^2
Fe = (9×10^9 * 0.00125 * 0.00333) / 3.62^2
Fe = (0.0000374625 * 10^9) / 13.1044
Fe = 37462.5 / 13.1044
Fe = 2858.7726N
Answer:
2858.7726 N
Explanation:
acellus
A graduated plank of length 90cm sits on a knife edge at 40cm mark. When a load of 50g is placed at 20cm, find the mass that will balance the plank at 70cm length.
Answer:
33.3 g ≈ 33 g
Explanation:
Please see attached photo for explanation.
From the attached photo, M is the mass that we must obtain to balance the plank.
The mass, M can be obtained as follow:
Anticlockwise moment = clockwise moment
Anticlockwise moment = 50 x 20
Clockwise moment = M x 30
Anticlockwise moment = clockwise moment
50 x 20 = M x 30
Divide both side by 30
M = (50 x 20)/30
M = 33.3 g ≈ 33 g
Therefore, the mass that will balanced the plank at the 70 cm length is appropriately 33 g
Plz help me with question 3
Answer:
C. 110 - 140
Explanation:
Answer:
i think the best answer is c
Levi observed properties of four different waves and recorded observations about each one in his chart. A 2-column table with 4 rows. The first column labeled Wave has entries W, X, Y, Z. The second column labeled Observations has entries travels fastest through metal, travels fastest through air, travels more slowly through water than air, travels more slowly at cool temperatures. Which statement is best supported by the table? Wave W and Y are light waves, Wave Z is a sound waves, and it is impossible to tell what kind of wave Wave X is. Wave W is a light wave, Waves X and Y are sound waves, and it is impossible to tell what kind of wave Wave Z is. Waves W and Z are sound waves, and Waves X and Y are light waves. Wave W is a sound wave, Waves X and Y are light waves, and it is impossible to tell what kind of wave Wave Z is.
Answer:
Wave W is a sound wave, Waves X and Y are light waves, and it is impossible to tell what kind of wave Wave Z is.
Explanation:
W travels fastest through metal
X travels fastest through air,
Y travels more slowly through water than air
Z travels more slowly at cool temperatures
W appears to be sound wave as sound travels fastest through metal .
X appears to be light wave as light travels fastest in air .
Y also appears to be light wave as speed of light is reduced when it passes from air to water .
Z It is impossible to tell anything about the nature of Z wave .
Answer:
d
Explanation:
A boat floats south on the Amazon River at a speed of 6 m/s. The boat and
passengers have a combined mass of 540 kg.
a. What is the momentum of the boat? (Remember, momentum is a vector
quantity.)
b. The passengers paddle backward, reducing the speed to 4 m/s. What was the
impulse applied to the boat by the paddling?
Explanation:
Take south to be negative.
a. Momentum is mass times velocity.
p = mv
p = (540 kg) (-6 m/s)
p = -3240 kg m/s
p = 3240 kg m/s south
b. Impulse = change in momentum
J = Δp
Since the mass is constant:
J = mΔv
J = (540 kg) (-4 m/s − (-6 m/s))
J = 1080 kg m/s
J = 1080 kg m/s north
Which of the following scientists introduced the concept of absolute zero?
A.lord kelvin
B.edwin Hubble
C.jonhannes kelper
D. Albert Einstein
Answer:
A. lord kelvin
Explanation:
In 1848, Kelvin used this as a basis for an absolute temperature scale. He defined "absolute" as the temperature at which molecules would stop moving, or "infinite cold." From absolute zero, he used the same unit as Celsius to determine the increments.
Absolute zero cannot technically be achieved. However, scientists have been able to lower the temperature of matter to just a fraction of a Kelvin above absolute zero through techniques such slowing down particles using lasers.