Answer:
[tex]\Rightarrow L=70 .03472 cm[/tex]
Explanation:
For convenience, let's represent the thermal expansion coefficient by [tex]\alpha[/tex], i.e. [tex]????=\alpha[/tex].
Given that, for steel [tex]\alpha =1.24\times 10^{-5}[/tex] °[tex]C^{-1}[/tex],
initial length, [tex]L_0=70 cm[/tex], initial temperature, [tex]T_0=70[/tex] °[tex]C[/tex], and the final temperature, [tex]T=110[/tex] °[tex]C[/tex].
Let the length of the rod at [tex]T=110[/tex] °[tex]C[/tex] be [tex]L[/tex].
Now, change in length, [tex]\Delta L=\alpha L_0 \Delta T[/tex]
[tex]\Rightarrow \Delta L=\alpha L_0 (T-T_0)[/tex]
[tex]\Rightarrow L-L_0=1.24\times 10^{-5}\times 70 (110-70)[/tex]
[tex]\Rightarrow L-70=1.24\times 10^{-5}\times 70 \times 40[/tex]
[tex]\Rightarrow L=70 + 0.03472 cm[/tex]
[tex]\Rightarrow L=70 .03472 cm[/tex]
Hence, the length of the rod at [tex]T=110[/tex] °[tex]C[/tex] be [tex]70.03472 cm[/tex].
A cylindrical tank of methanol has a mass of 60 kg and a volume of 75 L. Determine the methanol’s weight, den-sity, and specific gravity. Take the gravitational acceleration to be 9.81 m/s2. Also, estimate how much force is needed to accelerate this tank linearly at 0.25 m/s2.
Answer:
Weight = 588.6 N
Density = 800 kg/m³
Specific Gravity = 0.8
Force = 147.15
Explanation:
W = mg
W = 60 * 9.81
W = 588.6 N
Volume from L to m³ would be
75 L = 75 * 1/1000
75 L = 0.075 m³
Recall, density = mass/volume, so then, density of methanol is.
Density = 60/0.075
Density = 800 kg/m³
Specific gravity, SG is equal to
SG = density of methanol/density of water
SG = 800/1000
SG = 0.8
the force needed to accelerate the tank, F = ma
F = 588.6 * 0.25
F = 147.15 N
Therefore, the needed variables are
Weight = 588.6 N
Density = 800 kg/m³
Specific Gravity = 0.8
Force = 147.15
A car drove 200 km east on an interstate highway, then was finally able to make an
exit and drove for another 70 km to the north before reaching their destination.
What was the direction of car's resultant displacement?
Answer:
70.66°Explanation:
To find the direction of the displacement vector, we have to solve for the ratio of both displacements, and furthermore the inverse tangent of the ratio.
Given data
200km east represents the x axis
70 km north represents y axis
the direction of the resultant is given as
∅= tan-1x/y
∅=tan-1 200/70
∅= tan-120/7
∅= tan-12.85
∅= 70.66°
hence the direction of the resultant is 70.66°
Which method is the typical first step when scientists communicate their scientific results? placing the results on an Internet site to maximize readership distributing the results in press releases to make them well established submitting the results to a scientific journal for a peer review declaring the results in a TV interview for public feedback
Answer:
Option C (submitting the results to a scientific journal for a peer review) is the correct choice.
Explanation:
If a researcher or a scientist decides to transmit his conclusions depends on a variety of considerations. At either the conclusion of the day, the scientist should concentrate on the final use of an individual's findings before settling on how to transmit it, either through science papers, announcements at professional journals, or personally with the public.Scientists often prefer to submit their articles to professional conferences rather than just going via scientific publications.The other solutions offered are not relevant to the situation in question. But the latter is the best answer.
Answer:
it is letter c
Explanation:
1. A roller coaster car rapidly picks up speed as it rolls down a slope. As it starts down the slope, its
speed is 4 m/s. But 3 seconds later, at the bottom of the slope, its speed is 22 m/s. What is its
average acceleration?
Answer:
6 m/s²
Explanation:
Average acceleration = change in velocity / change in time
a = Δv / Δt
a = (22 m/s − 4 m/s) / 3 s
a = 6 m/s²
Answer:tryna get points don't mind me
Explanation:
Unlike velocity, speed is scalar, which means it is described by
Answer:
Magnitude
Explanation:
Scalar quantitys have no direction only a size aka magnitude
A wind turbine with a rotor diameter of 40 m produces 90 kW of electrical power when the wind speed is 8 m/s. The density of air impinging on the turbine is 1.2 kg/m3. What fraction of the kinetic energy of the wind impinging on the turbine is converted to electrical energy
Answer:
0.233
Explanation:
Given that
Diameter of rotor, d = 40 m
Power of rotor, P = 90 kW
Speed of the wind, v = 8 m/s
Density of air, p = 1.2 kg/m³
It is a known fact that
KE = ½mv², where mass flow rate, m
m = p.A.v, where Area, A
A = πd²/4
A = (3.142 * 40²)/4
A = 3.142 * 1600/4
A = 3.142 * 400
A = 1256.8 m², substitute for A in the mass flow rate equation
m = p.A.v
m = 1.2 * 1256.8 * 8
m = 12065.28, substitute for m in the KE equation
KE = ½mv²
KE = ½ * 12065.28 * 8²
KE = 12065.28 * 32
KE = 386088.96 W or
KE = 386.1 kW
Fraction of kinetic energy converted to electric energy is
Fraction = Electric Power / Total KE
Fraction = 90 / 386.1
Fraction = 0.233
Ryan places 0.150 kg of boiling water in a thermos bottle. How many kgs of ice at –12.0 °C must Ryan add to the thermos so that the equilibrium temperature of the water is 75?a. 0.0436 kgb. 0.0713 kgc. 0.0233 kgd. 0.0265 kge. 0.625 kg
Answer:
The value is [tex] m_i = 0.0234 \ kg [/tex]
Explanation:
Generally from the calorimetry principle we have that
[tex]Heat \ loss\ by\ ice = heat\ gained\ by\ water\[/tex]
So here heat gained water is mathematically represented as i.e
[tex]Q_w = m_w * c_w * (T_w - T )[/tex]
substituting 0.150 kg for [tex]m_w [/tex] , 4200 J/kg.°C for [tex]c_w [/tex] , 100°C for [tex]T_w [/tex] and 75°C for T
We have
[tex]Q_w = 0.150 * 4200 * (100 - 75 )[/tex]
[tex]Q_w =15750 \ J [/tex]
The Heat loss by the ice is mathematically represented as
[tex]Q_i = Q_1 + Q_2 + Q_3[/tex]
Here [tex]Q_1[/tex] is the energy to move the ice to its melting point which is evaluated as
[tex]Q_1 = m_i * c_i * ( T_o -T_i)[/tex]
Here [tex]m_i [/tex] is the mass of ice
[tex]c_i [/tex] is the specific heat of ice with value [tex]2.05 * 10^3 J/kg.°C[/tex]
[tex]T_o [/tex] temperature of ice at melting point with value 0°C
[tex]T_i [/tex] is the temperature of ice with value -12°C
[tex]Q_2[/tex] is the energy to move the ice from its its melting point to liquid which is evaluated as
[tex]Q_2 = m_i * L[/tex]
Here L is the Latent heat of melting of ice with value [tex]334 * 10^3 J/kg [/tex]
[tex]Q_3[/tex] is the energy to move the ice from liquid to the equilibrium temperature which is evaluated as
[tex]Q_1 = m_i * c_w * ( T -T_o)[/tex]
So
[tex]Q_i = m_i [ c_i * ( T_o -T_i) + L + c_w * ( T -T_o) ] [/tex]
=> [tex]Q_i = m_i [ 2.05 * 10^3 * ( 0 -(-12)) + 334 * 10^3 + 4200 * ( 75 - 0) ] [/tex]
From
[tex]Heat \ loss\ by\ ice = heat\ gained\ by\ water\[/tex]
We have that
[tex] m_i * 673600 =15750 [/tex]
=> [tex] m_i = \frac{15750}{673600} [/tex]
=> [tex] m_i = 0.0234 \ kg [/tex]
The amount of ice at –12.0 °C must Ryan add to the thermos so that the equilibrium temperature of the water is 75 - 0.0233 kg
The calorimetry principle we have thatheat is given by water = heat is received by ice
=>
Given:
mass of boiling water [tex]m_w = 0.150 kg[/tex]
temperature of ice [tex]T_i = - 12^0C[/tex]
Known:
specific heat of water [tex]c_w = 4.2 \times 10^3 J/kg-^0C[/tex] the Initial temperature of boiling water [tex]T_w = 100^0C[/tex]mass of ice = [tex]m_i[/tex]specific heat of ice [tex]c_i = 2.05 \times 10^3 J/kg-^0C[/tex] Latent heat of melting of ice [tex]L = 334 \times 10^3 J/kg[/tex] Melting point of ice [tex]T = 0^0C[/tex] Equilibrium temperature T = 75 CSolution:placing value in the formula:
=>
=>
= 0.0233 kg
Thus, the amount of ice at –12.0 °C must Ryan add to the thermos so that the equilibrium temperature of the water is 75 - 0.0233 kg
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What does Rockstrom mean by the need to "bend the curves"?
Answer: Rockstrom meant that it's going to be a challenging decade and that people will need to work hard and also bend the curve by thinking around the curve.
Explanation:
Some years ago, Johan Rockström, who was the executive director of Stockholm Environment Institute, and a professor at Stockholm University, was the head of an international team that was assembled in defining planetary boundaries.
The that was gathered to speak regarding issues that pertained to the Earth ane how it can be protected from being infiltrated ad protecting it from failing. During the conversation, Rockstrom said that it's going to be a challenging decade and that people will need to work hard and also bend the curve by thinking around the curve.
The gravitational pull of the sun on Earth keeps Earth orbiting around the sun. Which statement is correct about the force that Earth exerts on the sun?
Explanation:
The gravitational force exerted by the sun on the earth keeps the earth moving or orbiting around the sun in its orbit. This force is same with force with which the earth pulls the sun or exerts on the sun.
But the sun does not orbit around the earth because of this force since the sun is more massive then earth but the earth is less massive and it is accelerated by this massive force of the sun and moves around the sun in its orbit.
Answer:
Earth pulls the sun towards itself with a force equal to the ratio of the mass of the sun to the mass of Earth
bond formed when atoms share one or more pairs of electrons, but atoms do not always share electrons equally
Answer:
Polar covalent bond or just covalent bond
Explanation:
A bicyclist, traveling with a constant speed, covers 61.Om in 7.80s.
Determine all unknowns.
S =
7.82
m/s
d =
61
m
t =
Answer:
The velocity is 7.82 m/sExplanation:
In this problem, we are going to solve for the velocity since what we are given as parameters are:
1. Distance covered s= 61m
2. time taken to cover the distance t= 7.8 secs
we know that the expression for velocity is given as
velocity= distance/time
We then substitute the given data into the formula to solve for velocity.
velocity= 61/7.8
velocity= 7.82 m/s
The velocity is 7.82 m/sIn a house, a circuit often includes multiple electrical outlets which are parallelconnected to a single voltage source. Each of these circuits also contains a 15-A circuit breaker. Design a parallel-connected circuit which shows three electrical outlets connected to a voltage source with a circuit breaker. What is the advantage of having outlets parallel-connected, and why is a circuit breaker connected in series with the voltage source
Answer:
In parallel circuits, if one element has a problem, it can be eliminated and the rest of the elements continue to work.
Explanation:
There are two ways to connect electrical circuits, in series and in parallel.
Series circuits have the problem that when one element is damaged, the entire circuit is interrupted and runs out of power.
In parallel circuits, if one element has a problem, it can be eliminated and the rest of the elements continue to work.
In Breaker it is connected in series so that when some maintenance is needed, all the energy can be interrupted simultaneously and if some equipment tries to consume a lot of energy, the circuit prevents this action by interrupting the energy of the entire circuit
Electrons are important to electric current because they are able to
Given a 45 45 90 prism with index of 1.5, immersed in air. The hypotenuse acts as the reflecting face by TIR. A ray of light enters horizontal (perpendicular to one of the non- hypotenuse faces) hitting the hypotenuse at 45º and is reflected. If the original ray is now the center of a converging bundle of rays, converging toward the original intersection point on the hypotenuse, what full convergence angle (in air) is allowed, if TIR at the hypotenuse is to be preserved for the whole bundle of rays?
Answer:
83.6°
Explanation:
For the ray to be totally internally reflected, at the boundary, the angle of refraction is 90. Using the law of refraction where
n₁sinθ₁ = n₂sinθ₂ where n₁ = refractive index of prism = 1.5, θ₁ = critical angle in prism, n₂ = refractive index of air = 1 and θ₂ = refractive angle = 90°.
So, substituting these values into the equation,
n₁sinθ₁ = n₂sinθ₂
1.5 × sinθ₁ = 1 × sin90
1.5 × sinθ₁ = 1
sinθ₁ = 1/1.5
sinθ₁ = 0.6667
θ₁ = sin*(0.6667)
θ₁ = 41.8°
So, for total internal reflection, an incidence angle of 41.8° is required. So, a full convergence angle of 2 × 41.8° = 83.6° is required for the whole bundle of rays.
The
reflex causes a
newborn to turn toward the source of any
touching that occurs around his mouth.
Answer:
rooting reflex
Explanation:
prettysure
Which of the following is a physical property? 1.flammability 2.acidity 3.color 4.rusting
Answer:
Color is a physical property, the rest are chemical properties.
A person makes ice tea by adding ice to 1.8 kg of hot tea, initially at 80°C. How many kilograms of ice, initially at 0.00°C, are required to bring the mixture to 10°C? The heat of fusion of ice is 334 kJ/kg, and we can assume that tea has essentially the same thermal properties as water, so its specific heat is 4190 J/(kg·K).
Answer:
The required mass of ice is 12.5 kg.
Explanation:
Mass of hot tea, [tex]m_{t}[/tex] = 1.8 kg
Initial temperature of hot tea = 80°C = 353 K
Initial temperature of ice = 0.00°C = 273 K
Final temperature of mixture = 10°C = 283 K
Heat of fusion of ice, L = 334 kJ/kg
Specific heat capacity of tea, [tex]c_{t}[/tex] = Specific heat capacity of water = 4190 J/kg/K
Heat lost tea = Heat gained by ice
[tex]m_{t}[/tex][tex]c_{t}[/tex]Δ[tex]T_{t}[/tex] = [tex]m_{i}[/tex]L + [tex]m_{i}[/tex][tex]c_{i}[/tex]Δ[tex]T_{t}[/tex]
[tex]m_{t}[/tex][tex]c_{t}[/tex]Δ[tex]T_{t}[/tex] = [tex]m_{i}[/tex] (L + [tex]c_{i}[/tex]Δ[tex]T_{t}[/tex])
1.8 x 4190 x (353 - 283) = [tex]m_{i}[/tex](334 + (4190 x (283 - 2730))
1.8 x 4190 x 70 = [tex]m_{i}[/tex](334 + (4190 x 10))
527940 = 42234[tex]m_{i}[/tex]
[tex]m_{i}[/tex] = [tex]\frac{527940}{42234}[/tex]
= 12.5004
[tex]m_{i}[/tex] = 12.5 kg
The required mass of ice is 12.5 kg.
The required amount of ice to bring the mixture to 10°C is 12.5 kg.
Given data:
The mass of hot tea is, m' = 1.8 kg.
The initial temperature of hot tea is, T = 80°C = 353 K.
The initial temperature of ice is, T' = 0°C = 273 K.
The final temperature of mixture is, T'' = 10°C = 283 K.
The heat of fusion of ice is, h = 334 kJ/kg.
The specific heat of water is, c = 4190 J/kg·K.
Apply the condition of thermal equilibrium which says that the heat released by the hot tea will be gained by the ice.
Heat lost by tea = Heat gained by ice
[tex]m'c(T-T'') = mh +mc(T''- T')[/tex]
Here, m is the mass of ice.
Solving as,
[tex]1.8 \times 4190 \times (353-283) = (m \times 334) +(m \times 4190(283- 273))\\\\527940 = 42234m\\\\m = 12.5 \;\rm kg[/tex]
Thus, we can conclude that the required amount of ice to bring the mixture to 10°C is 12.5 kg.
Learn more about the thermal equilibrium here:
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You are riding in a car that is moving at 50 m/s north.
You pull a gun out while driving and fire a bullet north at 100 m/s. If the ground is the frame of refernce, then the bullet is traveling at
m/s relative to the ground
Answer:
the bullet is traveling at 150 m/s relative to the ground
Explanation:
The two velocities are pointing in the same direction (both pointing North) therefore, they should add.
Then, from the ground frame of reference the bullet is travelling at: 50 m/s + 100 m/s = 150 m/s
What example represents a healthy alternative to curb nicotine cravings?
O candy bars
O potato chips
O sugar-free gum
o chewing tobacco
Answer:
C.sugar-free gum
Explanation:
How is pressure related to the area
Samus is exploring the planet Zebes in the star system Metroid Prime (where the laws of physics are the same as on Earth and in our universe) in a ship moving at constant velocity. She turns on her headlamps as she encounters some strange fog. Ridley, the villain lying in wait, is at rest with respect to Samus. The speed of the light from Samus's headlamps as measured by Ridley depends most importantly on
Answer:
c. the speed of light in a vaccum
Explanation:
The complete question is...
Samus is exploring the planet Zebes in the star system Metroid Prime (where the laws of physics are the same as on Earth and in our universe) in a ship moving at constant velocity. She turns on her headlamps as she encounters some strange fog. Ridley, the villain lying in wait, is at rest with respect to Samus. The speed of the light from Samus's headlamps as measured by Ridley depends most importantly on
a. the speed of light in the fog
b. the speed of light of Samus's ship
c. the speed of light in a vaccum
d. the speed of Samus with respect to the ether
e. the total addition of speeds of Samus's ship, the planet Zebes, and the system Metroid Prime.
According to relativity,
1. The laws of physics are the same for all observers in any inertial frame of reference relative to one another.
2. The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the light source.
This means that The speed of the light from Samus's headlamps as measured by Ridley depends most importantly on the speed of light in a vacuum.
7. Starting at rest, a car accelerates at 5.5m/s/s for 12s. What is its
velocity at the end of 12s? *
Answer:
66 m/s
Explanation:
v=u+at
= 0 + 5.5 * 12
= 66 m/s
Point charges of 16.7 nC and 47.3 nC are placed 0.500 m apart. What is the electric field halfway between them? Indicate direction by a positive or a negative value. Keep in mind that a positive vector is one directed to the right and a negative vector is one directed to the left. Your answer should be a positive or a negative number with two decimal places, do not include the unit. Hint: 1 nC = 10-9 C
Answer:
-4320
Explanation:
Using the formula for electric field between two points
E = kq/r²
The electric field at a midpoint, say x, is
E(x) = [(k * 16.7*10^-9)/0.5²] - [(k * 47.3*10^-9)/0.25²]
E(x) = [k * (16.7*10^-9 - 47.3*10^-9)/0.25²]
E(x) = [(k * -30.6*10^-9)/0.0625]
E(x) = [(9*10^-9 * -30.6*10^-9)/0.0625]
E(x) = -270/0.0625
E(x) = -4320
Therefore, we can conclude that the electric field, halfway in between them is -4320
Which of these is an example of acceleration? A a bicyclist turning around a corner B a car traveling south with its cruise control set C a bus traveling north at 25m/s D a helicopter waiting to take off
The answer is A.
Acceleration means when you go faster in speed. Since the bicyclist is turning, he has to slow down but when he finishes turning, he is going to pedal harder and gain more speed. This is called Acceleration.
Best of Luck!
Answer:
a
Explanation:
Two aluminum soda cans are charged and repel each other, hanging motionless at an angle. Which of the forces on the left can has the greatest magnitude? T FE they are all the same impossible to tell mg Changed: Your submitted answer was incorrect. Your current answer has not been submitted.
Answer:
the tension is the greatest force the system
Explanation:
For this exercise we use Newton's second law, in the equilibrium condition, this means that the acceleration is zero a = 0
X-axis (horizontal)
FE - Tₓ = 0
Fe = Tₓ
Y axis (vertical)
[tex]T_{y}[/tex] - W = 0
T_{y} = W
let's use trigonometry for the stress components
sin θ = Tₓ / T
Tₓ = T sin θ
cos θ = T_{y} / T
T_{y} = T cos θ
we substitute
FE = T sin θ
W = T cos θ
Since the sine and cosine function have values between 0 and 1, the voltage must be greater than the electrical force and greater than the weight of the body.
Therefore the tension is the greatest force the system
Two forces P and Q act on an object of mass 9.00 kg with Q being the larger of the two forces. When both forces are directed to the left, the magnitude of the acceleration of the object is 1.20 m/s2. However, when the force P is directed to the left and the force Q is directed to the right, the object has an acceleration of 0.600 m/s2 to the right. Find the magnitudes of the two forces P and Q in newtons.
Answer:
P = 2.7 N
Q = 8.1 N
Explanation:
Q > P
Both the forces are acting towards the left
Net force = Q + P
Applying newton's 2nd law
net force = mass x acceleration
Q + P = 9 x 1.2 = 10.8 ----------------- ( 1 )
In the second case Q is acting towards the left and P acts towards the right
so they act in opposite direction
Hence net force = Q - P
Applying newton's 2nd law
net force = mass x acceleration
Q - P = 9 x .6 = 5.4 -------------------- ( 2 )
Adding ( 1 ) and ( 2 )
2 Q = 16.2
Q = 8.1 N
From ( 1 )
8.1 + P = 10.8 N .
P = 2.7 N
A person is wandering in woods and records his movements as a sequence of displacements: d1 is 351 m, 35.0° north of east; d2 is 252m, 55.0° west of north; d3 is 178 m, 35.0° south of west; and d4 is 253 m, 15.0° north of west. Find his displacement going back to his starting point straight.
Answer:
18.64
Explanation:
In a study of the effect of lighting on work productivity, the workers were told
that the lights would be changed on Monday, and researchers would measure
their response. The fact that the workers produced more than ever might not
be due to the lighting, but to the:
A. placebo effect
B. Hawthorne effect.
C. hypothesis theory,
D. informed consent theory.
Answer:
B. Hawthorne effect.
Explanation:
APEX
Answer:
b
Explanation:
Apex as always :)
Copper wire is a good electrical
(
Answer:
yes also good for pennies
Explanation:
Need Help with this physics question, just a written response
Answer:
Explanation:
According to Newton's third law, every action has an equal and opposite reaction
so it tells us that the force exerted by the earth on the spacecraft is equal to the force exerted by the spacecraft on the earth. But we do not see the earth moving towards the spacecraft because the inertia of the spacecraft is very less than the inertia of the earth.
