Answer:
2 and 8
Explanation:
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Derivation 1.2 showed how to calculate the work of reversible, isothermal expansion of a perfect gas. Suppose that the expansion is reversible but not isothermal and that the temperature decreases as the expansion proceeds. (a) Find an expression
Answer:
(a) The work done by the gas on the surroundings is, 17537.016 J
(b) The entropy change of the gas is, 73.0709 J/K
(c) The entropy change of the gas is equal to zero.
Explanation:
(a) The expression used for work done in reversible isothermal expansion will be,
where,
w = work done = ?
n = number of moles of gas = 4 mole
R = gas constant = 8.314 J/mole K
T = temperature of gas = 240 K
= initial volume of gas =
= final volume of gas =
Now put all the given values in the above formula, we get:
The work done by the gas on the surroundings is, 17537.016 J
(b) Now we have to calculate the entropy change of the gas.
As per first law of thermodynamic,
where,
= internal energy
q = heat
w = work done
As we know that, the term internal energy is the depend on the temperature and the process is isothermal that means at constant temperature.
So, at constant temperature the internal energy is equal to zero.
Thus, w = q = 17537.016 J
Formula used for entropy change:
The entropy change of the gas is, 73.0709 J/K
(c) Now we have to calculate the entropy change of the gas when the expansion is reversible and adiabatic instead of isothermal.
As we know that, in adiabatic process there is no heat exchange between the system and surroundings. That means, q = constant = 0
So, from this we conclude that the entropy change of the gas must also be equal to zero.
Explanation:
g A child bounces a 50 g super ball on the sidewalk. The velocity change of the super bowl is from 27 m/s downward to 17 m/s upward. If the contact time with the sidewalk is 1 800 s, what is the magnitude of the average force exerted on the superball by the sidewalk
Answer:
The average force exerted on the superball by the sidewalk is 0.00122 N.
Explanation:
Given;
mass of the super ball, m = 50 g = 0.05 kg
initial velocity of the super bowl, u = -27 m/s (assuming downward motion to be negative)
final velocity of the super bowl, u = 17 m/s (assuming upward motion to be positive)
time of motion, t = 1800 s
The average force exerted on the superball by the sidewalk is given by;
[tex]F = ma\\\\F = \frac{m(v-u)}{t} \\\\F = \frac{0.05(17-(-27))}{1800}\\\\ F = \frac{0.05(44)}{1800}\\\\F = 0.00122 \ N[/tex]
Therefore, the average force exerted on the superball by the sidewalk is 0.00122 N.
g (a) Calculate the block's final speed when it reaches the bottom of the frictionless inline. Keep 2 decimal places.
Answer:
Explanation:
The question is incomplete. Here is the complete question with attachment below.
In the above figure on the LEFT side, a block (mass = 2.8 kg) starts from rest at the top of a frictionless inline and slides to the bottom. The height of the incline is h=6.5 m, angle
A spring is stretched from rest and released. Which of the following describes the
frequency of the spring?
A:the speed of the spring as it passes through the equilibrium position
B: the number of times the spring moves up and down in 1 second
C:the time it takes the spring to compress and then expand once
D: the number of coils on the spring
Explanation:
you have given two questions which one to answer
Isaac walks 4 blocks north. Then he turns around and walks 1 block south.
Which of the following correctly describes Isaac's motion?
A. Isaac walked a distance of 5 blocks, and his displacement was 3
blocks north.
B. Isaac walked a distance of 5 blocks, and his displacement was 5
blocks.
C. Isaac walked a distance of 3 blocks, and his displacement was 3
blocks north.
D. Isaac walked a distance of 3 blocks north, and his displacement
was 5 blocks.
Answer:
Isaac walked a distance of 5 blocks, and his displacement was 3 blocks north.
Explanation:
Distance is what he covered from the beginning, while displacement was what he covered in a specific direction
What type of research based on approach that used to describe variables rather than to test a predicted relationship between variables?
Answer:
Correlational research can be used to see if two variables are related and to make predictions based on this relationship.
Magnets are usually made up of which material
A. plastic
B. iron ore
C. copper
D. gold
Answer:
B. iron ore
Explanation:
Hope this helps
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the mass of the Moon is 7.35x1022kg and the mass of the Earth is 5.97x1024kg. The Moon’s orbit distance is 3.84x108m. What is the gravitational force on the Moon by the Earth? What is the gravitational force of the Earth on the Moon?
ok no ok no ok no ok no ok no ok no ok no
A spring gun is able to launch a 7.0 gram marble to a vertical height of 22 mmeasured from the compressed point of the marble). If the spring iscompressed 8.0 cm from its relaxed state, what will be the spring constant
Answer: Spring constant = 472N/m
Explanation:
The change in gravitational potential energy by the spring is given as = mgh
where m= 7.0 g = 7 X 10 -3kg
g= 9.8m/s
h= 22m
Gravitational potential energy= mgh
= 7.0 x 10^-3 X 9.8 x 22 = 1.5092 J
Remember that change in gravitational potential energy by the spring =elastic potential energy
Therefore, Potential energy P. E = 1/2 K x²
where K= CONSTANT
x= 8.0
2 X 1.5092 J / (8.0 X 10^-2)²= 471.625 ROUNDED TO 472 N/m
A 1400.0 kg car crests a 3200.0 m pass in the mountains and briefly comes to rest. The car descends 1000 m before climbing and cresting a 2800 m pass. (a) Neglecting friction, what should the speed of the car be at the top of the second pass? (b) Find the actual speed of the car if the work due to nonconservative forces is – 5 x106 J.
Answer:
a) v = 88.54 m/s
b) vf = 26.4 m/s
Explanation:
Given that;
m = 1400.0 kg
a)
by using the energy conservation
loss in potential energy is equal to gain in kinetic energy
mg × ( 3200-2800) = 1/2 ×m×v²
so
1400 × 9.8 × 400 = 0.5 × 1400 × v²
5488000 = 700v²
v² = 5488000 / 700
v² = 7840
v = √7840
v = 88.54 m/s
b)
Work done by all forces is equal to change in KE
W_gravity + W_non - conservative = 1/2×m×(vf² - vi²)
we substitute
1400 × 9.8 × ( 3200-2800) - (5 × 10⁶) = 1/2 × 1400 × (vf² -0 )
488000 = 700 vf²
vf² = 488000 / 700
vf² = 697.1428
vf = √697.1428
vf = 26.4 m/s
Write a haiku
poem
explaining
why graphing
is useful.
If you are
able, share
your poem
with others.
Answer:
Explanation:
graphing is helpful
helps visualize the line
of your equation
3. How are force, work, and power related?
Answer:
Work is the energy needed to apply a force to move an object a particular distance, where force is parallel to the displacement. Power is the rate at which that work is done.
Answer: Work is the energy needed to apply a force to move an object a particular distance, where force is parallel to the displacement. Power is the rate at which that work is done.
Explanation:
What equation relates mechanical energy, thermal energy, and total energy when there is friction present in a system?
A solid nonconducting sphere of radius R carries a charge Q distributed uniformly throughout its volume. At a certain distance rl (r
(A) E/8
(B) E 78.
(C) E/2
(D) 2E
(E) 8E
Answer:
A ) E/8
Explanation:
If the sphere of radius R carries charge Q, then the volumetric charge density is:
ρ₁ = [Q/ (4/3)*π*R³]
Therefore the net charge inside r ( r < R ) is:
q₁ = ρ * (4/3)*π*r³
And E = K * q₁/r K = 9,98 *10⁹ [N*m²/C²]
E = K * ρ * (4/3)*π*r³/r
E = K * ρ * (4/3)*π*r²
If now the charge is distributed over a sphere of radius 2R
ρ₂ = [Q/ (4/3)*π*(2R)³]
ρ₂ = [Q/ (4/3)*π*8*R³]
Then ρ₂ < ρ₁ in fact ρ₂ = (1/8)*ρ₁
The electric field depends on the net charge enclosed by a gaussian surface, and the distance between the net charge and the considered point, ( considering the net charge as being at the center of the gaussian surface) In this case, there was no distance change then
E₂ = E₁/8
The right answer is lyrics A ) E/8
Why wouldn't carbon dating work to determine the age of the earth?
A) Carbon dating works best on other planets
B) The half life of carbon is too short
C) The age of the earth cannot be determined
D) The half life of carbon is too long.
Answer:
The half-life of carbon is too short.
Explanation:
The answer is B.
Your TV has a resistance of 10 ohms and a wall voltage of 120 V. How much current and power does it use
Answer:
Current used is 12 ampere.
Power is 1440 watts.
Explanation:
To find the current used by the TV.
Current (I) = voltage/resistance
Current= 120/10
Current is 12Ampere.
To get power used by the TV,
Power = voltage × current.
= 120× 12
Power = 1440 watts.
What is the energy contained in a 1.30 m3 volume near the Earth's surface due to radiant energy from the Sun
Answer:
The energy contained is 5.856 x 10⁻⁶ J
Explanation:
Average energy density of electromagnetic radiation per unit volume is given by the equation;
[tex]U_{avg} = \frac{1}{2} \epsilon _o E_o[/tex]²
where;
[tex]\epsilon _o[/tex] is permittivity of free space
[tex]E_o[/tex] is maximum electric field strength, this can be calculated from the intensity of sun reaching the Earth's surface.
[tex]E_o = \sqrt{\frac{2I}{\epsilon_o C} }[/tex]
The intensity of sun reaching the Earth is 1350 W/m²
[tex]E_o = \sqrt{\frac{2*1350}{8.885*10^{-12}*3*10^8 } } \\\\E_o = 1008.96 \ V/m\\[/tex]
Average energy density of electromagnetic radiation per unit volume;
[tex]U_{avg} = \frac{1}{2} \epsilon_o E_o^2\\\\U_{avg} = \frac{1}{2} (8.85*10^{-12})(1008.96)^2\\\\U_{avg} = 4.505 *10^{-6} \ J/m^3[/tex]
The energy contained in a 1.30 m³ volume is given by;
E = (4.505 x 10⁻⁶)(1.3)
E = 5.856 x 10⁻⁶ J
Therefore, the energy contained is 5.856 x 10⁻⁶ J
QUESTION 2
At the end of an investigation, what should be done if the results do NOT support the hypothesis?
O A Repeat your investigation to ensure your results are accurate and then modify your hypothesis if necessary.
OB. Repeat your investigation over and over again until you get the results that will support your original hypothes
O C. Check your measurement tools to ensure they are working.
OD. Change the topic of your investigation to one that will yield results that support a hypothesis.
Answer:
A. Repeat your investigation to ensure your results are accurate and then modify your hypothesis if necessary.
Explanation:
Having results that do not support the hypothesis is a common occurrence.
Hypotheses always depend on the data and experiment. If at the end of an investigation the results do not support the hypothesis, the investigation should be be repeated to further confirm this discovery.
And if there is still no correlation, then the hypothesis is not a reasonable explanation for the investigation and should be modified or rejected if necessary.
2. For a rotating rigid body, which of the following statements is NOT correct?
a. All points along a rotating rigid body move with constant linear speed.
b. Points along a rotating body have same angular velocities.
c. Points along a rotating body move through the same angle in equal time intervals.
d. All points have the same angular acceleration.
Answer:
dasgfwe
Explanation:
A 1200 kg car is accelerating at 4.5 m/s2. What is the force on the car?
Answer:
5400 N
Explanation:
f=ma
f= 1200*4.5
f=5400N
Big Bird decided to visit three of his friends. He got in his car and drove to Elmo’s house. It took Big Bird 10 minutes to drive the 5 miles. After visiting with Elmo for 30 minutes, he headed to Bert and Ernie’s house. This drive covered 15 miles and took 20 minutes. After a 25 minute stay, Big Bird headed to Cookie Monster’s house. The Cookie Monster’s house was 10 miles away and it took Big Bird another 15 minutes to get there. Because Cookie Monster wasn’t home, he was only there for 5 minutes. Big Bird then headed home, a trip that was 20 miles away and took him 25 minutes. What was the average speed for Big Bird’s whole trip (include his visiting time)?
Average speed =
(total distance)
divided by
(total time).
That's 28.57 miles per hour.
The average speed of Big Bird is 0.384 miles/minute.
What is average speed?The average speed of a body is the ratio of the total distance travelled and the time taken to travel that distance.
Average speed = total distance travelled/time takenThe total distance travelled = 50 miles
total time taken = 130 minutes
Average speed = 50 miles/130 minutes = 0.384 miles/minute.
Therefore, the average speed of Big Bird is 0.384 miles/minute.
Learn more about average speed at: https://brainly.com/question/747081
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Define reflection of sound?
Explanation:
When sound travels in a given "medium", it would touch the surface of another "medium" and will bounce back in some other direction, this occurrence is called the reflection of sound.
Someone help
Match the definition to the term.
1.
the noun that follows the verb and answers the questions
whom or what
linking verb
2. a word that expresses action
sentence
3. who or what the sentence is about
predicate noun
4.
a noun that indicates to or for whom or what something is
done
predicate adjective
5. follows a linking verb and renames the subject
direct object
subject
6. follows a linking verb and describes a subject
verb that joins a subject and a predicate noun or predicate
7.
adjective
indirect object
8. expresses a complete thought
verb
Answer:
Explanation:
No 1 is linked to the option provided at no 5.
A direct object is the noun that follows the verb and answers the question.
No 2 is linked to the option provided at no 8.
A verb is a word that expresses action.
No 3 is linked to the option provided at no 5.
The subject is what or whom the sentence is about.
No 5 is linked to the option provided at no 3.
A predicate noun follows a linking verb, and renames the subject.
No 6 is linked to the option provided at no 4.
A predicate adjective follows a linking verb, and describes a subject.
No 7 is linked to the option provided at no 1.
A linking verb joins a subject and a predicate.
No 8 is linked to the option provided at no 2.
A sentence expresses a complete thought....
Answer:
predicate noun: follows a linking verb and describes a subject
verb: a word that expresses action
direct object: a noun that indicates to or for whom or what something is done
sentence: expresses a complete thought
predicate adjective: verb that joins a subject and a predicate noun or predicate adjective
subject: who or what the sentence is about
indirect object: follows a linking verb and renames the subject
linking verb: the noun that follows the verb and answers the questions whom or what
Hope this helps!
Correct me if I'm wrong:)
the radius of the earth social
A boat initially moving at 10 m/s accelerates at 2 m/s for 10 s. What is the velocity of the boat after 10 seconds?
Answer:
30 m/s
Explanation:
v = u + at
given that,
u = 10 m/s (initial speed)a = 2 m/s^2 t = 10sv =?(final speed)v = 10 + ( 2 × 10)
v = 10 + 20
v = 30 m/s
why do some athletes get injuries before and after the game?
Answer:
they don't strech so they tear a muscle when they perform
Explanation:
A football team lost 3 yards on their first play. On the second play, 10 yards were gained. On the third play the quarterback got tackled behind the line of scrimmage and lost 6 yards. What was their net gain or loss after the three plays?
+1yd
Explanation:
Kfgjjh
Answer:
+1 YD
Explanation:
-3 + 10 - 6 = 1
Can anybody tell me what I'm suppose to do. I click start the numbers comes up to the right
am I right? be honest
Answer:
I chose c because it is the greater slope at point c
Type your response in the box.
Different kinds of substances have different properties. Compare and contrast the electrical properties of salts, acid , metals
Answer:
salts do not conduct electricity. unless u try to dissociate its ions,it cannot.
metals are good conductors of electricity.
acids also conduct electricity if you dissociate them into ions.