Temperatures of four liquid substances are shown in the chart.
Which statement is best supported by the data in the chart?
A) Substance X will transfer thermal energy to substance Y mainly through radiation if they are mixed.
B) Substance Y will transfer thermal energy to substance Z through conduction if they are mixed.
C) Substance X will transfer thermal energy to substance W through radiation if they are placed near each other.
D) Substance W will transfer thermal energy to substance X through conduction if they are mixed.
Answers
For those of you taking the course on Edge, the right answer is D.
Answer: D) Substance W will transfer thermal energy to substance X through conduction if they are mixed.
Explanation: Thermal energy is the energy possessed by an object by virtue of its temperature. It is transferred from a hotter object to a colder object till both the bodies attain the same temperature.
Radiation occurs when thermal energy is transferred by electromagnetic waves. Conduction occurs when thermal energy is transferred when two objects are in direct contact.
Thus Substance W at a temperature of [tex]40^0C[/tex] will transfer thermal energy to substance X at a temperature of [tex]37^0C[/tex] through conduction if they are mixed as they are in direct contact.
Related Questions
As thunder travels away from a lightning channel, the amplitude (loudness) of the sound ____ by ____ as the distance from the channel doubles.
Answers
"As thunder travels away from a lightning channel, the amplitude (loudness) of the sound DECREASES by A FACTOR 4 as the distance from the channel doubles."
In fact, the intensity of a sound wave follows an inverse square law: it means it is inversely proportional to the square of the distance, [tex]1/r^2[/tex], where r is the distance from the source. We see from the formula that, if we double the distance, the intensity gets a factor [tex]1/4[/tex], which means that the intensity decreases by a factor 4.
As a sound wave moves away from its source, its amplitude decreases due to an inverse square relationship, meaning it is divided by four as the distance doubles. The decrease is also due to energy spread over a larger area, absorption by objects, and conversion into thermal energy.
Explanation:As thunder, which is a form of sound wave, travels away from a lightning channel, the amplitude (loudness) of the sound decreases by one-quarter as the distance from the channel doubles. This happens due to an inverse square relationship with distance from the source. Essentially, as the sound wave moves further away from its origin, the intensity declines because the energy of the wave is spread over a larger area.
Moreover, the amplitude of a sound wave decreases with distance from its source also due to factors like absorption by objects and conversion to thermal energy by the viscosity of air. Thus, the further away you are from the source of the sound, in this case, the lightning channel, the softer the thunder will sound.
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Electromagnetic waves are ____ waves consisting of changing electric and magnetic fields
Combing equal amounts of the three primary pigments produces ?
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and if you mix yellow, magenta, and cyan you get black
Electromagnetic waves are transverse waves consisting of changing electric and magnetic fields, and combining primary pigments results in black or dark gray.
Explanation:Electromagnetic waves are transverse waves that consist of changing electric and magnetic fields. These fields oscillate at right angles to each other and to the direction of wave propagation. The movements of these fields generate each other, and this interaction forms the electromagnetic wave.
The second part of your question, concerning pigments, seems a bit out of context as it deals with a subject in color theory, from the field of Art or Physics. However, I can tell you that combining equal amounts of the three primary pigments (cyan, yellow, and magenta) results in the production of black or a very dark gray.
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a summer thunderstorm has begun! it’s raining. lighting cracks through air. a few seconds later you hear booms of thunder. why do you see the lighting before you hear the thunder?
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Hope this helps.
What is menat by the age of the universe? how old is the universe?
Answers
No one is exactly sure. But its estimated to be 14 billion years old.
The distance from the top of one sound wave to the top of the next sound wave is called
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A spring with a spring constant of 1.8 × 102 n/m is attached to a 1.5 kg mass and then set in motion.
a.what is the period of the mass-spring system?
b.what is the frequency of the vibration
Answers
m = 1.5kg
T = ?
f =?
T = (2π) sqrt(m/k)
T = (2π) sqrt(1.5/(1.8x 10^2)) = .5732s
F = 1/T
F = 1÷.5732=1.744Hz
Part A: The time period of the mass-spring system is 0.573 seconds.
Part B: The frequency of the vibration of the mass-spring system is 1.75 Hz.
Time Period and FrequencyGiven that the mass of the spring is 1.5 kg and the spring constant is 1.8 × 10^2 n/m.
Part AThe period of the mass-spring system is given by the formula.
[tex]T=2\pi\sqrt{\dfrac {m}{k}}[/tex]
Where m is mass and k is spring constant.
Substituting the values in the above equation, we get the time period.
[tex]T = 2 \times 3.14 \times \sqrt{\dfrac {1.5}{ 1.8 \times 10^2}}[/tex]
[tex]T = 0.573 \;\rm s[/tex]
Hence the time period of the mass-spring system is 0.573 seconds.
Part BThe frequency of the vibration is given below.
[tex]f = \dfrac {1}{T}[/tex]
[tex]f = \dfrac {1}{0.573}[/tex]
[tex]f = 1.75 \;\rm Hz[/tex]
Hence the frequency of the vibration of the mass-spring system is 1.75 Hz.
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When an object moves at a very high speed relative to an observer, its measured length in the direction of motion is contracted. t true?
Answers
When an object is moving towards the observer, its measured wavelength decreases,(it is not correct if measured length) because the waves are compressed.
Which is a characteristic that makes electromagnetic waves and water waves different
Answers
Why is newton's first law of motion sometimes called the lae of inertia?
Answers
This law talks about the tendency of an object to resist any change in its state of rest or uniform motion, this is called Inertia. Thus Newton's 1st law of motion is also called the Law of Inertia
Final answer:
Newton's first law of motion, also known as the law of inertia, states that an object at rest remains at rest and an object in motion remains in motion unless acted upon by an external force.
Explanation:
Newton's first law of motion states that a body at rest remains at rest or, if in motion, remains in motion at a constant velocity unless acted on by a net external force. This law is also known as the law of inertia. Inertia is the tendency of an object at rest to remain at rest or, if moving, to remain in motion at constant velocity. Inertia is related to an object's mass.
A block with mass m =7.4 kg is hung from a vertical spring. when the mass hangs in equilibrium, the spring stretches x = 0.23 m. while at this equilibrium position, the mass is then given an initial push downward at v = 3.9 m/s. the block oscillates on the spring without friction. 1 what is the spring constant of the spring?
Answers
k = -F/x, where k = spring constant, F = weight = mg = 7.4*9.81 = 72.594 N, x = spring displacement = 0.23 m
Substituting;
k = - 72.594/0.23 = -315.63 N/m
The negative sign shows that the force opposes spring constant.
When a front wheel drops off the roadway you should?
Answers
When a front wheel drops off the roadway, stay calm, maintain a firm grip on the steering wheel, slow down gradually, and carefully steer back onto the road while checking for traffic.
When a front wheel drops off the roadway while you are driving, there are several steps you should follow to safely regain control:
Stay calm: Avoid any sudden movements or panicking, which can worsen the situation.
Hold the steering wheel: Keep a firm grip on the steering wheel to maintain control of the vehicle.
Decelerate gradually: Slowly lift your foot off the accelerator to decrease speed, but do not brake suddenly as this can cause further loss of control.
Slowly steer back: Gradually steer the vehicle back onto the roadway once you have slowed down sufficiently.
Check for traffic: Always ensure it is safe to merge back onto the road by checking for other vehicles.
By following these steps, you can safely recover from your front wheel dropping off the roadway and minimize the risk of an accident.
What does the word “adverse” mean in the following sentence? Adverse reactions, such as fever and headache, can occur if the medication is not taken properly.
a. important
b. happy
c. tricky
d. unfavorable?
Answers
Answer: d. unfavorable
Explanation:
Here, the word adverse means unfavorable. This is because of the fact that if the medication is not taken properly it is likely to affect the health of the living being and may lead to the development of unfavorable symptoms or drastic health complications such as fever and headache.
Answer:
B
Explanation:
This answer is correct because, Robinson was 36 and starting to feel the effects of his age. In 1956 he did not dominate the league as much as he used to, partially because of the adverse effects of the diabetes he suffered from. It says he was not playing as well because of the negative effects of diabetes so the answer is B, to negatively prevent.
In which region of the electromagnetic spectrum is most of earth's outgoing terrestrial radiation?
Answers
Most of Earth's outgoing terrestrial radiation is in the infrared region of the electromagnetic spectrum, particularly around 11,000 nm. This infrared radiation is a key component of the Earth's energy budget and contributes to the greenhouse effect.
Explanation:Most of Earth's outgoing terrestrial radiation is in the infrared region of the electromagnetic spectrum. The temperature of Earth's surface determines the wavelength and the intensity of the radiation it emits. Since the Earth's surface is cooler than the sun, its radiation peaks at longer wavelengths, specifically around 11,000 nm (nanometers), which falls within the infrared range. Approximately 99% of Earth's outgoing radiation is between 3,000 nm and 40,000 nm. It is important to note that while this radiation is invisible to the human eye, it plays a critical role in the Earth's energy budget and is key to the greenhouse effect. Gases such as water vapor, carbon dioxide, and methane absorb part of the Earth's radiation, which in turn warms the atmosphere.
A violin string that is 50.0 cm long has a fundamental frequency of 440 Hz. What is the
speed of the waves on this string?
Answers
[tex]\lambda=2 L[/tex]
In our problem, L=50.0 cm=0.50 m, therefore the wavelength of the wave is
[tex]\lambda = 2 \cdot 0.50 m = 1.00 m[/tex]
And the speed of the wave is given by the product between the frequency and the wavelength of the wave:
[tex]v=\lambda f = (1.00 m)(440 Hz)=440 m/s[/tex]
Answer:
30800 m/s
Explanation:
correct answer
Sound from source a has twice the frequency of sound from source
b. compare the wavelengths of sound from the two sources.
Answers
Which term does not identify a vector quantity?
Answers
--> €
--> £
--> ¢
--> ¥
--> Ü
--> Δ
--> Σ
--> Φ
--> π
--> Ω
--> ω
--> √
--> ∞
--> $
--> °C
--> °F
Calculate the number of moles of oxygen in a 12.5-l tank if the pressure is 25325 kpa and the temperature is 22°c
Answers
[tex]pV=nRT[/tex]
where
p is the gas pressure
V is its volume
n is the number of moles
R is the gas constant
T is the absolute temperature of the gas
For the gas in our problem:
[tex]p=25325 kPa = 2.53 \cdot 10^4 kPa = 2.53 \cdot 10^7 Pa[/tex]
[tex]V=12.5 L = 12.5 \cdot 10^{-3} m^3[/tex]
[tex]T=22^{\circ}C = 295 K[/tex]
If we plug the data into the equation, we can find the number of moles of the gas:
[tex]n= \frac{pV}{RT}= \frac{(2.53 \cdot 10^7 Pa)(12.5 \cdot 10^{-3} m^3)}{(8.31 J/mol K)(295 K)}=129 mol [/tex]
Using the Ideal Gas Law (PV=nRT), we calculate that there are approximately 128.94 moles of oxygen in a 12.5 L tank at a pressure of 25325 kPa and a temperature of 22°C.
To calculate the number of moles of oxygen in a 12.5 L tank at a pressure of 25325 kPa and a temperature of 22°C, we use the Ideal Gas Law, which is given by:
PV = nRT
Here, P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.
First, convert the temperature to Kelvin:
T = 22°C + 273.15 = 295.15 K
Next, convert the pressure to atm:
P = 25325 kPa × 0.00986923 atm/kPa ≈ 249.94 atm
Using the gas constant R = 0.0821 L·atm/(mol·K), we substitute the values into the Ideal Gas Law:
n = PV / RT = (249.94 atm × 12.5 L) / (0.0821 L·atm/(mol·K) × 295.15 K)
Solving this:
n ≈ (3124.25 atm·L) / (24.229215 mol·K)
n ≈ 128.94 moles
Therefore, under the given conditions, there are approximately 128.94 moles of oxygen in the tank.
A group of friends is celebrating New Years when one of them pulls out a gun and fires it into the air. One of the bullets comes down and strikes another member of the group in the head, killing him. What is the cause of death?
A) homicide
B) accidental
C) gunshot wound
D) cerebral hemorrhage
Determine the manner of death based on the following description:
Man shot during robbery. Man stabilizes. Develops pneumonia, followed by kidney failure, liver failure, and finally death. He had prior lung and heart disease, and probably would have survived if not for these diseases.
A) accident
B) homicide
C) natural
D) suicide
The following situations are presented to a medical examiner. In which situation is the medical examiner most likely to gather more evidence before determining the manner of death?
A) 18-year-old male recovered in alley with gunshot wound to back of head
B) 25-year-old
Answers
(But it were also unintentional, I'm leaning towards B as well..but more on C)
2. C, he wasn't intentionally meant to die by the gunshot wound, he developed illnesses then and died later of them! (Followed by his already had illnesses)
3. A, a younger body is more healthy and easier to find the cause of death, while an older individual could be much harder and already have many problems.
(I'm just using processes of text evidence)
Answer:
1. C
2. C
3. A
Explanation:
1. In the given question the cause of death is gunshot. because of gunshot on the head wound develops and person died. So here answer would be option c: gunshot wound.
2.In this question man survived after gunshot(maybe his immunity reduced) and after sometime he develops pneumonia, kidney failure and liver failure, here cause of death is these diseases so cause is natural. option c would be the right answer.
3. For a medical examiner most likely to gather more evidences before determining the manner of death would be a 18-year-old boy. Because his body is completely developed and full of immunity( in normal cases).
What is the approximate distance from the center of the milky way galaxy to the sun? select one:
a. 0 light years - the sun is at the center
b. 280 light years
c. 2,800 light years
d. 28,000 light years
e. 280,000 light years?
Answers
Trees in the mid-west change colors and lose their leaves in the cooler parts of the year.
What kinds of trees lose their leaves?
A)
deciduous
B)
evergreen
C)
nonvascular
D)
nonwoody
Answers
GIVE ME BRAINLIEST NOW
A girl throws a rock horizontally, with a velocity of 10 m/s, from a bridge. it falls 20 m to the water below. how far does the rock travel horizontally before striking the water, assuming negligible air resistance?
Answers
Given:
vix=10m/s
dy= 20m
What you are looking for is horizontal distance or dx.
The formula for vertical distance is:
[tex]dx=vi_{x}t[/tex]
Where:
dx= horizontal distance
vix= initial horizontal velocity
t=time
But when you look at your problem, you do not have time. Now for time, you need to use the formula:
[tex]t= \sqrt{ \frac{2dy}{g} } [/tex]
g in this equation is a constant. It is the acceleration due to gravity which has the value of 9.8m/s^2.
Now we first need to get time:
[tex]t= \sqrt{ \frac{2dy}{g} } [/tex]
[tex]t= \sqrt{ \frac{2(20m}{9.8m/s^{2}} } [/tex]
[tex]t= \sqrt{ 4.08163265} [/tex]
[tex]t=2.02s [/tex]
Now that you have time, all you need to do is insert that into our equation for horizontal distance.
[tex]dx=vi_{x}t[/tex]
[tex]dx=(10m/s)(2.02s)[/tex]
[tex]dx=20.20m[/tex]
The horizontal distance of the rock will be 20.20m.
The rock strikes the water after traveling approximately 20.3 meters horizontally. This is calculated using principles of physics related to projectile motion, with the separate vertical and horizontal movements taking place simultaneously and independently.
Explanation:The physics problem you've described deals with the concept of projectile motion. In this scenario, the horizontal and vertical movements of the rock can be analyzed separately. The vertical displacement doesn't affect the horizontal one given the negligible air resistance.
First, let's find the time it takes for the rock to hit the water below. We can use the equation of motion, d = 0.5*g*t², where g is the acceleration due to gravity (9.8 m/s²), and d is the vertical displacement (20 m). Solving for t, we get approximately 2.03 seconds.
Then, to find the horizontal distance that the rock traveled, we use the formula for velocity (v = d/t), rearranged to solve for distance: d = v*t. Here, v is the initial velocity of the rock (10 m/s) and t is the previously calculated time (2.03 seconds). Completing the calculation, we find that the horizontal distance the rock travels before striking the water is approximately 20.3 meters.
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How can a series of synoptic weather maps be used to predict the future location of a low pressure center?
Answers
A series of synoptic weather maps help us to predict the future location of low-pressure systems by tracking the direction of the wind, the front locations, and the centers of high pressure, and also the location of the jet stream and how strong it is. The synoptic weather maps are used to acquire a complete photo of the place under surveillance. Along with computers, the maps are used to define a forecast.
A train with mass 1000kg is moving at 15 m/s south. A second train engine with a mass of 500 kg is sitting at rest on the tracks ahead. What is the magnitude of the total momentum of the entire system? Assume that after the trains crash the first train comes to a stop at the point of the crash. How fast does the second train slide? Assume that after the crash the trains stick together and slide as one. How fast to they slide? Assume that after the crash the second train is sliding at 20 m/s south. What is the velocity of the first train?
Answers
Total momentum is
[tex]p=(1000kg)*(15m/s) = 15000(kg*m/s)[/tex]
When the first train comes to a complete stop, it is an elastic collision. We can use conservation of momentum to solve for the velocity of the second train.
[tex]15000(kg*m/s)=500v v=30m/s[/tex]
If they stick completely, then it is an inelastic collision. Here we have to combine the mass of the two trains and solve for the velocity.
[tex]15000(kg*m/s) = (1000+500)v v= 10m/s[/tex]
Finally, if the train is 20m/s then what is the velocity of the first train. Just like before, we can solve using conservation of momentum.
[tex]15000=(500kg)(20m/s)+1000v v=5m/s[/tex]
A motorcycle traveling at 15 m/s accelerates at a constant rate of 4.0 m/s over a distance of 50 meters. What is the final velocity of the motorcycle
Answers
v^2 = u^2 + 2as ----- v = final velocity, u = initial velocity, a = acceleration, s = distance covered.
Using the vales given;
v^2 = 15^2 + 2*4*50 = 625
v = Sqrt (625) = 25 m/s
How does lubricating a machine affect the output work from that machine? how would the input and output forces be affected?
Answers
the in put and out put force may increase as it's easier for the machine to work due to less friction
By lubricating its components, a machine can operate more effectively and send less energy to the environment as heat by reducing friction between its parts.
Due to the machine's simplicity of use and less friction, the input and output forces might both increase.
What is lubrication?To reduce wear and tear and friction in a contact between two surfaces, lubrication is a procedure or technique that uses a lubricant. The area of tribology includes the study of lubrication as a discipline.
Solid body interactions are decreased through the design of lubrication mechanisms, such as fluid-lubricated systems, which carry the given load either entirely or partially by hydrodynamic or hydrostatic pressure (and consequently friction and wear). Different lubrication regimes can be recognized depending on how far the surfaces have separated.
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Light cannot escape the intense gravitational pull of a _____.
Answers
hope it helped
Light cannot escape the intense gravitational pull of a black hole.
What is a black hole?A black hole is a region of space where gravity is so strong that nothing, not even light, can escape. Black holes are formed when massive stars collapse at the end of their lives. The force of gravity is so strong that even the light waves cannot escape the black hole's event horizon.
The event horizon is the boundary around a black hole from which nothing, not even light, can escape. The event horizon is a sphere of space-time around the black hole where the escape velocity is equal to the speed of light.
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The height of the washington monument is measured to be 170 m on a day when the temperature is 30.0°c. what will its height be in meters on a day when the temperature falls to −16.0°c? although the monument is made of limestone, assume that its thermal coefficient of expansion is the same as marble's.
Answers
ΔL = αLΔT, ΔL = change in length or height, α = coefficient of linear thermal expansion, ΔT = Change in temperature.
In the current case;
α = 2.5*10^-6 /°C (for Marble)
L = 170 m at 30.0°C
ΔT = 30 - (-16) = 46°C
Substituting;
ΔL = 2.5*10^-6 *170*46 = 0.01955 m
Height at -16°C = 170 - 0.01955 = 169.98 m
The current through inductance L is given by I=I0e−t/τ
A.) Find an expression for the potential difference ΔVL across the inductor.
B.) Evaluate ΔVL at t=0s , if L=15mH , I0=36mA , and τ=1.1ms
C.) Evaluate ΔVL at t=1ms , if L=15mH , I0=36mA , and τ=1.1ms
D.) Evaluate ΔVL at t=2ms , if L=15mH , I0=36mA , and τ=1.1ms
E.) Evaluate ΔVL at t=3ms , if L=15mH , I0=36mA , and τ=1.1ms
Answers
The potential difference (voltage) across the inductor is given by VL = L*(dI/dt), which for this specific question evaluates to VL = -L*I0*(e^-t/τ) / τ. Applying the given values at different time intervals, we can find VL values at t=0s, t=1ms, t=2ms, and t=3ms.
Explanation:The current through an inductor is given by I=I0e−t/τ. Let's answer your questions one by one:
A) The potential difference (voltage) across the inductor is given by VL = L*(dI/dt). For this particular problem, it would be VL = -L*I0*(e^-t/τ) / τ. This equation results from the fact that the rate of change of current through an inductor is related to the voltage across it.
B) At t=0s, VL would evaluate to -L*I0 / τ.
C) At t=1ms, VL would evaluate to -L*I0*(e^-1) / τ.
D) At t=2ms, VL would evaluate to -L*I0*(e^-2) / τ.
E) And finally, at t=3ms, VL would evaluate to -L*I0*(e^-3) / τ.
These calculations use the given constants L=15mH, I0=36mA, and τ=1.1ms.
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The potential difference across the inductor is given by the equation VL = -L*I0*e^(-t/τ)*(1/τ). Plugging in L=15mH, I0=36mA, and τ=1.1ms, evaluations for t=0, 1ms, 2ms, and 3ms yield -0.49V, -0.27V, -0.15V, and -0.08V respectively.
Explanation:The potential difference across the inductor, ΔVL, can be determined by using Faraday's law which states that the EMF in a circuit is equal to the rate of change of magnetic flux. In this case, it corresponds to:
VL = L*(dI/dt) = L * d/dt [I0*e^(-t/τ)] = -L*I0*e^(-t/τ)*(1/τ)
From this equation, the potential difference can be evaluated at different times.
At t=0s: ΔVL = -L*I0*1/τ = - (15x10^-3)*(36x10^-3)/1.1x10^-3 = - 0.49 V At t=1ms: ΔVL = -L*I0*e^(-t/τ)*(1/τ) = - (15x10^-3)*(36x10^-3)*e^(-1/1.1)(1/1.1x10^-3) = -0.27 V At t=2ms: ΔVL = - (15x10^-3)*(36x10^-3)*e^(-2/1.1)(1/1.1x10^-3) = -0.15 V At t=3ms: ΔVL = - (15x10^-3)*(36x10^-3)*e^(-3/1.1)(1/1.1x10^-3) = -0.08 V Learn more about Potential Difference across Inductor here:https://brainly.com/question/31595289
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Knowing the constant g what will the gravitational force between two masses be if the gravitational force between them is 36n and the distance is tripled? answer
Answers
[tex]F=G \frac{m_1 m_2}{r^2} [/tex]
where
G is the gravitational constant
m1 and m2 are the two masses
r is the separation between the two masses
We see that the force is proportional to the inverse of the square of the distance: [tex]F \sim \frac{1}{r^2} [/tex]
therefore, if the distance is tripled:
r'=3r
The force decreases by a factor 1/9:
[tex]F \sim \frac{1}{(3r)^2}= \frac{1}{9} \frac{1}{r^2} [/tex]
Since the original force was 36 N, the new force will be
[tex]F' = \frac{1}{9} (36 N)= 4 N [/tex]
Final answer:
The gravitational force between the two masses will be 4 N.
Explanation:
The gravitational force between two masses is given by the formula F = G * (M1 * M2) / R^2, where F is the force, G is the universal gravitational constant, M1 and M2 are the masses of the two bodies, and R is their separation. In this case, the force between the two masses is 36 N. If the distance between them is tripled, the new force can be found by calculating F' = G * (M1 * M2) / (3R)^2. Since R^2 is 9 times larger than (3R)^2, the new force will be 1/9 of the original force. Therefore, the gravitational force between the two masses will be 4 N.
what is the atomic number z of 73li?
Answers
[tex] ^7 _3 {Li} [/tex] means that the element is Lithium (Li), 7 corresponds to its mass number (sum of protons and neutrons), 3 corresponds to its atomic number (number of protons in the nucleus).
The problem asks for the atomic number (Z) of this isotope: based on what we said previously, the answer is 3.