When an aluminum bar is connected between a hot reservoir at 720 K and a cold reservoir at 358 K, 3.00 kJ of energy is transferred by heat from the hot reservoir to the cold reservoir. (a) In this irreversible process, calculate the change in entropy of the hot reservoir._______ J/K
(b) In this irreversible process, calculate the change in entropy of the cold reservoir.
_______ J/K
(c) In this irreversible process, calculate the change in entropy of the Universe, neglecting any change in entropy of the aluminum rod.
_______ J/K
(d) Mathematically, why did the result for the Universe in part (c) have to be positive?
Answer:
a. -4.166 J/K
b. 8.37 J/K
c. 4.21 J/K
d. entropy always increases.
Explanation:
Given :
Temperature at hot reservoir , [tex]$T_h$[/tex] = 720 K
Temperature at cold reservoir , [tex]$T_c$[/tex] = 358 K
Transfer of heat, dQ = 3.00 kJ = 3000 J
(a). In the hot reservoir, the change of entropy is given by:
[tex]$dS_h= -\frac{dQ}{t_h}$[/tex] (the negative sign shows the loss of heat)
[tex]$dS_h= -\frac{3000}{720}$[/tex]
= -4.166 J/K
(b) In the cold reservoir, the change of entropy is given by:
[tex]$dS_c= \frac{dQ}{t_c}$[/tex]
[tex]$dS_c= \frac{3000}{358}$[/tex]
= 8.37 J/K
(c). The entropy change in the universe is given by:
[tex]$dS=dS_h+dS_c$[/tex]
= -4.16+8.37
= 4.21 J/K
(d). According to the concept of entropy, the entropy of the universe is always increasing and never decreasing for an irreversible process. If the entropy of universe decreases, it violates the laws of thermodynamics. Hence, in part (c), the result have to be positive.
At
room temperature, chlorine is a gas, bromine is a liquid, and
iodine is a solid. However, all
three elements share some
physical properties. They also
have very similar chemical
properties. They are grouped in the same column on the periodic table. What common property do
you observe?
Explanation:
One common property with all halogens in group 7 is that they are all non-metals.
Fluorine, chlorine, Bromine and Iodine are classified as non-metallic elements and they have a high electronegativity.
In chemical reactions, they are very reactive because they require just one electron to complete their octet configuration and be isoelectronic with noble gases.The most prominent observation from halogens is that they all non-metallic in nature.
A system of 4 electrons, 18 protons, and 4 neutrons has a net charge of?
Answer:
+ 14
Explanation:
18 protons make a positive 18 charge (+18)
4 electrons make a negative 4 charge (-4)
both combined give + 18 - 4 = + 14
The four neutrons don't carry net charge, so the addition of the electrons doesn' affect the net charge found above which still gives + 14.
A plane moves at a speed of 100 mi/h and takes flight on a 25 degree angle. What is the VERTICAL speed in mi/h? Round to the nearest whole number and DO NOT include units (Ex: 11).
Answer:
The vertical speed in mi/h is 42.
Explanation:
Rectangular Components of a Vector
A 2D vector can be expressed in several forms. The rectangular form gives its two components, one for each axis (x,y). The polar form gives the components as (r,θ) being r the magnitude and θ the angle.
The relationships between the coordinates of both systems are shown in the image below.
When the magnitude and angle of the vector are given, the rectangular components are calculated as follows:
[tex]v_x=v\cos\theta[/tex]
[tex]v_y=v\sin\theta[/tex]
Where v is the magnitude of the vector and θ is the angle with respect to the x positive direction.
We are given the magnitude of the velocity (the speed) at which a plane is moving as v=100 mi/h at an angle of θ=25°, the vertical component of the velocity is:
[tex]v_y=100\sin 25^\circ[/tex]
Calculating:
[tex]v_y=42.26\approx 42[/tex]
The vertical speed in mi/h is 42.
June does an experiment to study how salt affects the freezing point of water
Answer:
Salt melts ice and helps keep water from re-freezing by lowering the freezing point of water. This phenomenon is called freezing point depression. Salt only helps if there is a little bit of liquid water available. The salt has to dissolve into its ions in order to work.
Explanation:
The amount of time for a synchronous input to a flip-flop to be stable before the rising edge of clock is called the hold time. a) True b) False
Answer:
true
Explanation:
Answer:
true
Explanation:
You use an electron microscope in which the matter wave associated with the electron beam has a wavelength of 0.0173 nm. What is the kinetic energy of an electron in the beam, expressed in electron volts?
Answer:
The kinetic energy of an electron in the beam is 5.04 keV.
Explanation:
We need to find the velocity of the electron by using the De Broglie wavelength:
[tex] \lambda = \frac{h}{mv} [/tex]
Where:
λ: is the wavelength = 0.0173 nm
v: is the velocity
m: is the electron's mass = 9.1x10⁻³¹ kg
h: is the Planck constant = 6.62x10⁻³⁴ J.s
[tex] v = \frac{h}{m\lambda} = \frac{6.62 \cdot 10^{-34} J.s}{9.1 \cdot 10^{-31} kg*0.0173 \cdot 10^{-9} m} = 4.21 \cdot 10^{7} m/s [/tex]
Now, we can find the kinetic energy:
[tex] E_{k} = \frac{1}{2}mv^{2} = \frac{1}{2}9.1 \cdot 10^{-31} kg*(4.21 \cdot 10^{7} m/s)^{2} = 8.06 \cdot 10^{-16} J*\frac{1 eV}{1.6 \cdot 10^{-19} J} = 5038 eV = 5.04 keV [/tex]
Therefore, the kinetic energy of an electron in the beam is 5.04 keV.
I hope it helps you!
A falling ball has potential energy of 5 J and a kinetic energy of 10 J. What is the ball's mechanical energy?
What is the mass of a toy truck if 18 N of force is needed to accelerate the boat to
2 m/s2 ?
Answer:
9 kg
Explanation:
Force= Mass * Acceleration
18 N= Mass * 2 m/s^2
(18 N / 2 m/s^2) = Mass
Mass= 9 kg
Use the drop-down menus to complete each sentence.
A plant grows toward a sunny window. This response is an example of
✔ phototropism
.
Sometimes a plant grows around a tree for support. This response is an example of
✔ thigmotropism
.
The roots of a plant grow toward a water source. This response is an example of
✔ hydrotropism
.
The roots of a plant grow down into the soil. This response is an example of
✔ gravitropism
.
the answers are already there
Answer:
The correct answer is - phototropism, thigmotropism, hydrotropism, and gravitropism in order ( already match correctly).
Explanation:
phototropism is a phenomenon in which plants grow towards the light or sun which is accomplished by the hormone auxin in the cells far from the light.
Thigotropism is a type of plant growth that occurs around the tree to support itself which is a touch stimuli response.
The movement of the plant in the direction of the source of the water is known as hydrotropism. In which stimuli is humidity or the water concentration.
The movement of the plant or roots of the plants towards the soil or earth is known as gravitropism here gravity is the stimuli.
Answer:
Use the drop-down menus to complete each sentence.
A plant grows toward a sunny window. This response is an example of
phototropism
.
Sometimes a plant grows around a tree for support. This response is an example of
thigmotropism
.
The roots of a plant grow toward a water source. This response is an example of
hydrotropism
.
The roots of a plant grow down into the soil. This response is an example of
gravitropism
.
Explanation:
Describe and give an example of mutualism.
Describe and give an example of commensalism.
Describe and give an example of parasitism.
Describe and give an example of competition.
Describe and give an example of predation.
Answer:
Mutualism, commensalism, parasitism, competition, and predation.
Explanation:
mutualism- relationship between two or more organisms where both are benefited. Example-oxpecker with rhino/zebra. They eat bugs off of them which means that they are getting food, while the rhino/zebra are getting cleaned up with pest control.
commensalism- relationship between two organisms where one benefits and the other isn't benefited or harmed. EX- tree frogs use plants as protectioin.he frog is benefited, and the plant is neither harmed nor benefited. Remora fish have a disk on their heads that they use to attach themselves to larger animals for protection. The animals they attach to are neither harmed nor benefited.
parasitism- in a relationship where an organism benefits at the expense of the other. (one is benefited while the other is harmed) ex- fleas and ticks that live on cats and dogs, tape worms that live in people and animals that eat the food which means that the people aren't getting the food or nutrition that they eat. lice, etc
competition- interaction within organisms/species in which both the organisms/species are harmed and is apart of natural selection. Examples may include two males fighting over a mate, animals competing over food, limited habitats that they are fighting over, territory, etc.
predation- the preying of one animal on another. It's where the predator hunts and eats another organism which is its prey. categorized within-(1) carnivory, (2) herbivory, (3) parasitism, and (4) mutualism. Each type of predation can by categorized based on whether or not it results in the death of the prey.ex- owls hunting mice, wolves hunting rabbits, lion hunting gazelle, etc.
A spaceship of mass mm circles a planet of mass M in an orbit of radius R. How much energy is required to transfer the spaceship to a circular orbit of radius 3R?
Answer:
ΔE = GmM/3R
Explanation:
The absolute potential energy of an object in a planet's field is given as:
E = -GmM/2r
where,
E = Potential Energy
G = Universal Gravitational Constant
m = mass of spaceship
M = Mass of Planet
r = distance from surface of planet
Therefore, for initial state:
E = E₁ and r = R
E₁ = - GmM/2R
and for final state:
E = E₂ and r = 3R
E₂ = - GmM/6R
So, the required energy will be:
ΔE = E₂ - E₁ = - GmM/6R + GmM/2R
ΔE = GmM(- 1/6R + 1/2R)
ΔE = GmM/3R
what are the laws of newton
Answer:
Explanation:
These are the laws of Newton
Answer:
the first law, an object will not change its motion unless a force acts upon it. the 2nd one, the force of an object is equal to its mass times it acceleration. the 3rd one is when 2 objects interact, they apply forces to each other of equal magnitude and opposite direction.
what do we call the games that involve different manipulation skills like throwing,tossing,rolling,catching,running,jumping,hopping and stretching what is the answer A.puzzle game B.simulation games C.target games D.role-playing games
The volume of water in a measuring cyclinder is 50 ml .When a piece of stone is immeresed in the cyclinder the volume of water increases to 87.3ml. Calculate volume of stone.
Answer:
37.3ml
Explanation:
87.3 ml-50 ml=37.3ml
Answer:
ok
Explanation:
g
Lifting a stone block 146m to the top of the Great Pyramid required 146,000 J of work. How much work was done to lift the block halfway to the top?
A. 36,500 Joules
B. 73,000 Joules
C. 146,000 Joules
D. 292,000 Joules
Please help me.
Suppose the flow rate of blood in a coronary artery has been reduced to half its normal value by plaque deposits. By what factor has the radius of the artery been reduced, assuming no turbulence occurs?
Strategy
Assuming laminar flow, Poiseuilleâs law states that
Q = (p2 - p1)pir^4/8nl.We need to compare the artery radius before and after the flow rate reduction.
Answer:
1.18
Explanation:
The flow rate of blood is proportional to the fourth power of its radius as given the Poiseuille's law.
The law is :
[tex]$Q \propto r^4$[/tex]
It is given here that the flood flow rate is been reduced to half its normal value. Therefore, [tex]$Q_1 = \frac{1}{2}Q_2$[/tex]
So, for the radius [tex]$r_1$[/tex] and [tex]$r_2$[/tex], the ratios of their flow rates are :
[tex]$\frac{Q_1}{Q_2}=\frac{r_1^4}{r_2^4}$[/tex]
It is given that the flow rate is reduced to half. So we have,
[tex]$\frac{Q_1}{2Q_1}=\frac{r_1^4}{r_2^4}$[/tex]
or [tex]$r_2=2^{1/4}{r_1}$[/tex]
[tex]$r_2=1.18 \ r_1}$[/tex]
So the radius changes by a factor of 1.18
A net force F acts on a mass m and produces an acceleration a. What acceleration results if a net force 4F acts on a mass 6m?
Answer: The acceleration results if a net force of 4F acts on a mass of 6m is 2/3a.
Explanation:
Force exerted on an object can be defined as a pull or a push on an object which leads to it's displacement. Force is taken to be a vector quantity because it has both magnitude and direction. The formula which can be used to determine force exerted on an object in physics is:
F= mass( kg) × acceleration( m/ s²)
Acceleration is defined as the rate at which the velocity of an object changes. From the formula of force given above it can be determined by making it the subject of formula. Therefore acceleration= Force/ mass.
From the question,
Force= 4F
Mass= 6m
Therefore acceleration= F/m
= 4/6
Acceleration= 2/3a
The required magnitude of acceleration when force is 4F and mass is 6m is 2/3a.
Given data:
The magnitude of net force is, 4F.
The value of mass is, 6m.
Apply the Newton's second law which says that force exerted on an object can be defined as a pull or a push on an object which leads to it's displacement. Force is taken to be a vector quantity because it has both magnitude and direction. The formula which can be used to determine force exerted on an object in physics is
F = ma
a = F/m ..........................................(1)
here, a is the acceleration.
Solving as when the force becomes 4F and mass becomes 6m.
[tex](4F) = (6m) \times a'\\\\a '= \dfrac{4F}{6m}\\\\a '= \dfrac{2}{3}a[/tex]
Thus, the required magnitude of acceleration when force is 4F and mass is 6m is 2/3a.
Learn more about the Newton's Second law here:
https://brainly.com/question/13447525
A 20kg rock is sliding on a rough, horizontal surface at 8 m/s and eventually stops due to friction. the coefficient of kinetic friction between the rock and the surface is 0.200. what average power is produced by friction as the rock stops?
Answer:
156watts
Explanation:
M = 20
U = 0.200
Vo = 8.0
We are to get p
P = w/t
W = 1/2(vf²-Vo²)
The final velocity is 0
W =-1/2*20*8²
= -640J
Acceleration = -ug
= -0.200*9.8
= -1.96m/s^-2
We are to get t
t = 8/1.96
= 4.1s
P = w/t
= 640/4.1
= 156 watts
156watts is the average power that is produced by friction as the rock stops.
WHAT IS TRANS ATLANTIC SLAVE TRADE
Two manned satellites approach one another at a relative speed of 0.400 m/s, intending to dock. The first has a mass of 5.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity in meters per second?
Answer:
why do you think the senate changed the way it voted? What methods did the suf
why do you think the senate changed the way it voted? What methods did the suffragis
why do you think the senate changed the way it voted? What methods did the suffragists use to influence this change?
Two manned satellites approach one another at a relative speed of 0.400 m/s, intending to dock. The first has a mass of 5.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity in meters per second?
hi
lolTwo manned satellites approach one another at a relative speed of 0.400 m/s, intending to dock. The first has a mass of 5.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity in meters per second?ts use to influence this change?
Two manned satellites approach one another at a relative speed of 0.400 m/s, intending to dock. The first has a mass of 5.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity in meters per second?
hi
lolfragists use to influence this change?
Explanation:
Two manned satellites approach one another at a relative speed of 0.400 m/s, intending to dock. The first has a mass of 5.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. If the two satellites collide elastically rather than dock, what is their final relative velocity in meters per second?
hilol
What unbalanced force is needed to give a 976 kg vehicle an acceleration of 2.50 m/s2? ASAP
Answer:
2440 NExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 976 × 2.5
We have the final answer as
2440 NHope this helps you
A flat loop of wire consisting of a single turn of cross-sectional area 7.10 cm2 is perpendicular to a magnetic field that increases uniformly in magnitude from 0.500 T to 2.10 T in 1.07 s. What is the resulting induced current if the loop has a resistance of 1.60?
Answer:
The induced current is [tex]I = 0.00066 \ A[/tex]
Explanation:
From the question we are told that
The area is [tex]A = 7.10 \ cm^2 = 7.10 *10^{-4} \ m^2[/tex]
The initial magnetic field is [tex]B_i = 0.500 \ T[/tex]
The magnetic field after t =1.07 s is [tex]B_f = 2.10 \ T[/tex]
The resistance of the loop is [tex]R = 1.60 \ \Omega[/tex]
Generally the electromagnetic field induced is mathematically represented as
[tex]\epsilon = NA * \frac{B_f - B_i}{t}[/tex]
Where N is the number of turns which is 1 in the case of this question since there is only one loop
So
[tex]\epsilon = 1 * 7.10*10^{-4}* \frac{2.10 - 0.500}{1.07 }[/tex]
=> [tex]\epsilon = 0.00106 \ V[/tex]
Generally the value of the current is mathematically represented as
[tex]I = \frac{\epsilon}{R}[/tex]
[tex]I = \frac{0.00106}{1.60}[/tex]
[tex]I = 0.00066 \ A[/tex]
A magnet of mass 0.20 kg is dropped from rest and falls vertically through a 35.0 cm copper tube. Eddy currents are induced, causing the copper to warm up. The speed of the magnet as it emerges from the tube is 1.50 m/s. How much heat energy is dissipated to the environment?
Answer:
The energy lost to the environment is 0.461 J
Explanation:
Given;
mass of the magnet, m = 0.2 kg
height of fall, h = 35 cm = 0.35 m
initial speed of the magnet, u = 0
final speed of the magnet, v = 1.5 m/s
Initial energy of the magnet is given by;
E₁ = P.E₁ + K.E₁
E₁ = mgh₁ + ¹/₂mu²
E₁ = (0.2 x 9.8 x 0.35) + ¹/₂(0.2)(0)²
E₁ = 0.686 J
Final energy of the magnet as it emerges from the tube is given by;
E₂ = mgh₂ + ¹/₂mv²
E₂ = (0.2 x 9.8 x 0) + ¹/₂(0.2)(1.5)²
E₂ = 0 + 0.225 J
The energy lost to the environment is given by;
E = E₂ - E₁
E = 0.225 J - 0.686 J
E = -0.461 J (negative sign indicates lost energy to the environment)
Therefore, the energy lost to the environment is 0.461 J
1. When asteroids collided some of the broken materials fall into Earth's orbit. What do
astronomers call the debris when it hits planet Earth?
Answer:
meteoroids
Explanation:
when an asteroid (or really anything else) falls to earth, it is called a meteoroid
Which of the following describes the motion or change caused by a transformation from electrical to sound energy? (2 points) a A child listens to the music from a trumpet. b A dog howls to the siren from a police car. c A person moves their arm when they hear the buzz of a fly. d Music comes out from a television speaker.
Answer:
d.music comes out from a television speaker
Explanation:
because television use electricity (electrical energy) and produce sound (sound energy) that we hear while watching tv
Answer:
The answer would be (D) Music comes out from a television speaker.
Explanation:
This is because the TV uses electrical energy from where its plugged in. And the speaker is the sound energy which is caused by the TV to go with the show you are watching.
Hope this helps!
What is the approximate horizontal velocity at which the boy in the diagram
threw the ball?
a. +5m/s
b. +20m/s
c. +25m/s
d. +30m/s
Answer:
D
Explanation:
5+25=30
A rod is pivoted about its center and oriented horizontally. A 5.0-N force directed upward is applied 4.0 m to the left of the pivot and another upward 5.0-N force is applied 1.5 m to the right of the pivot. What is magnitude of the total torque about the pivot?
Answer:
The total torque is 27.5 Nm
Explanation:
Given;
5.0-N force directed upward is applied 4.0 m to the left of the pivot,
5.0-N force directed upward is applied 1.5 m to the right of the pivot,
Taking the moment about the pivot, the total torque is given by;
τ = Fr
where;
F is the appllied force
r is the radius of the force arm
τ = (5 N x 4 m) + (5 N x 1.5 m)
τ = 27.5 Nm
Therefore, the total torque is 27.5 Nm
A golf ball hit off a tee on level ground, lands 62 m away 3.0 later. What was the initial velocity of the golf ball?
62×3.0
think so not sure
2. An ambulance traveling at 20 m/s emits a sound at 500 Hz. What frequency does a person standing on the corner of a street detect?