Answer:
x = A cos (w \sqrt{2y_{o}/g})
a) maximun Ф= \sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
b) minimun Ф = [tex]\frac{\pi }{2}[/tex] - \sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
Explanation:
For this exercise let's use kinematics to find the time it takes for the mass to reach the floor
y = y₀ + v₀ t - ½ g t²
as the mass is released from rest, its initial velocity is zero (vo = 0) and its height upon reaching the ground is zero (y = 0)
0 = y₀ - ½ g t²
t = [tex]\sqrt{2y_{o}/g}[/tex]
The bucket-spring system has a simple harmonic motion, which is described by
x = A cos wt
in this expression we assumed that the phase constant (Ф) is zero
let's replace the time
x = A cos (w \sqrt{2y_{o}/g})
this is the distance where the system must be for the mass to fall into it.
a) The new system has a total mass of m ’= 3.0 kg, so its angular velocity changes
w = [tex]\sqrt{k/m}[/tex]
In the initial state
w = \sqrt{k/2}
When the mass changes
w ’= \sqrt{k/3}
the displacement in each case is
x = A cos (wt)
for the new case
x ’= A cos (w’t + Ф)
the phase constant is included to take into account possible changes due to the collision of the mass.
we see that this maximum expressions when the cosine is maximum
cos (w´t + Ф) = 1
w’t + Ф = 0
Ф = -w ’t
Ф = - [tex]\sqrt{k/3}[/tex] [tex]\sqrt{2y_{o}/g}[/tex]
\sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
b) the function is minimun if
cos (w’t + fi) = 0
w’t + Ф = π / 2
Ф = π / 2 - w ’t
Ф = [tex]\frac{\pi }{2}[/tex] - \sqrt{\frac{2}{3} \frac{2 y_{o} }{g} }
Look at this model of an atom. Where are the protons located and how many are there?
Answer:
protons are in the nucleus .
Explanation:
there are 6 protons
.
Calculate the potential energy of a 6 kg bowling ball suspended 3 m above the surface of the Earth.
Answer: 176.4 J
Explanation:
Wavelength is a measurement of ___________ , while period is a measurement of ___________ . *
Speed; time
Time; speed
Distance; time
Time; distance
Distance; speed
Speed; distance
distance ; time
Explanation:
wavelength is in metres [m]
period is in seconds [s]
An astronaut floating at rest in space throws a wrench in one direction and subsequently recoils back with a velocity in the opposite direction. Which of the following statements is/are true?
I. The velocity of the wrench is equal and opposite to the velocity of the astronaut.
Il. The momentum of the wrench is equal and opposite to the momentum of the astronaut.
III. The impulse applied to the wrench is equal and opposite to the impulse applied to the astronaut
a) ll and ill only
b) I only II only
c) I, II, and III
d) I and Il only
Answer:
a) ll and Ill only
Explanation:
Let the mass of the wrench = m
and the mass of the astronaut = M
Initially, the velocity of the astronaut and wrench are zero.
The astronaut throws the wrench in one direction and subsequently recoils back with a velocity in the opposite direction.
Let v and V be the velocity of the wrench and the velocity of the astronaut respectively.
In space, there is no external force acting, the momentum must be conserved.
So, m(0)+M(0)=m(v)+M(V)
So, 0=mv+MV
[tex]\Rightarrow mv=-MV[/tex] ...(i)
Here, the momentum of the wrench = mv, and the momentum of the astronaut= MV. The negative sign showing that both the momentum are in opposite direction.
Therefore, the momentum of the wrench is equal and opposite to the momentum of the astronaut.
According to Newton's second law, the rate of change of momentum = applied force.
Let it take [tex]\Delta t[/tex] seconds to change the momentum.
So, for the wrench
[tex]m(v-0)/\Delta t= F_w \\\\\Rightarrow m(v-0)=F_w\Delta t \\\\\Rightarrow mv=F_w\Delta t \cdots(ii)[/tex]
Here, [tex]F_w\Delta t[/tex] is the impulse applied to the wrench.
Similarly, for the astronaut
[tex]M(-V-0)/\Delta t= F_a[/tex] [negative sign (-V) for opposite direction]
[tex]\Rightarrow M(-V-0)=F_a\Delta t \\\\\Rightarrow -MV=F_a\Delta t[/tex]
Here, [tex]F_a\Delta t[/tex] is the impulse applied to the astronaut.
So, the impulse on the astronaut.
By using equations (i) and (ii)
[tex]F_a\Delta t=F_w\Delta t[/tex]
Therefore, the impulse applied to the wrench is equal and opposite to the impulse applied to the astronaut.
Hence, option (a) is correct.
Which of the following is an opinion about friction?
It always acts in the opposite direction as the motion of the object.
It stops objects on Earth from staying in motion forever.
It slows objects down too much.
It happens any time two objects are in contact.
Help me out please-
You'll get 40 points
My opinion about friction is that It always acts in the opposite direction as the motion of the object.
What is friction?Friction refers to the resistance of motion of one object that is moving relative to another object. Fricton has many application but it has also many disadvantages.
So we can conclude that friction is always acts in the opposite direction as the motion of the object.
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What is the turning effect of a force?
A force may cause an object to turn about a pivot. The turning effect of a force is called the moment of the force. Moments act about a pivot in a clockwise or anticlockwise direction.
Answer:
A force may cause an object to turn about a pivot. The turning effect of a force is called the moment of the force. Moments act about a pivot in a clockwise or anticlockwise direction.
Explanation:
A high-resistance material is used as an insulator between the conductors of a length of coaxial cable. The resistance material, which forms a hollow tube, has an inner radius a and an outer radius b, and the insulator provides a resistance R between the conductors. If a second insulator, made of the same material and having the same length, is made with double both the inner radius and the outer radius of the first, what resistance would it provide between the conductors
This question is incomplete, the complete question is;
A high-resistance material is used as an insulator between the conductors of a length of coaxial cable. The resistance material, which forms a hollow tube, has an inner radius a and an outer radius b, and the insulator provides a resistance R between the conductors. If a second insulator, made of the same material and having the same length, is made with double both the inner radius and the outer radius of the first, what resistance would it provide between the conductors
a) (In2)R
b) 4R
c) R/(In2)
d) 2R
e) R
Answer: Option e) R is the correct answer.
Explanation:
Given that;
Inner radius = a
Outer radius = b
Conical Cylinder
∫dR = ∫(edr/2πrL)
R = e/2πL In e |ᵇₐ
R = e/2πL In(b/a) ------------- let this be equation 1
Taking a look at the second cone
a' = 2a
b' = 2a
R' = e/2πL In(2b/2a)
{L = L'}
R' = e/2πL In(b/a) -------let this be equation 2
now lets compare the two equation
R = e/2πL In(b/a)
R' = e/2πL In(b/a)
so R' = R
Therefore Option e) R is the correct answer.
Two disks are rotating about the same axis. Disk A has a moment of inertia of 3.4 kg m^2 and an angular velocity of 7.2 rad/s. Disk B is rotating with an angular velocity of -9.8 rad/s. The two disks are then linked together without the aid of any external torques, so that they rotate as a single unit with an angular velocity of -2.4 rad/s. The axis of rotation for this unit is the same as that for the separate disks. What is the moment of inertia of disk B
Answer:
I = 4.4 kg*m^2
Explanation:
As no external torques are present, total angular momentum must be conserved, as follows:[tex]L_{o} = L_{f} (1)[/tex]
The initial angular momentum of the two disks rotating separately, can be written as follows:[tex]L_{o} =I_{A} * \omega_{oA} + I_{B} * \omega_{oB} (2)[/tex]
Replacing by the givens, we get:[tex]L_{o} = 3.4kg*m2 * 7.2rad/s + I_{B} * (-9.8 rad/s) (3)[/tex]
The final angular momentum Lf, as the axis of rotation remains the same, is the product of the moment of inertia of both disks rotating as one, and the common angular velocity ωf, as follows:[tex]L_{f} = (I_{A} + I_{B}) *\omega_{f} (4)[/tex]
Replacing by the givens, we get:[tex]L_{f} = (3.4 kg*m2 + I_{B} ) * (-2.4 rad/s) (5)[/tex]
From (3) and (5), we can solve for IB, as follows:IB = 4.4 kg*m2Good conductors have:
Question 9 options:
A) current moves easily
B) conserves energy-easy for electrons to move
C) all of the above
D) low resistance
Answer:
[tex]\boxed{\boxed{\sf all \ of \ the \ above }}[/tex]
MORE TO KNOW Materials that easily allow the current to pass through it are called Good conductor Materials that can pass the current but not as much as good conductor are called poor conductor Materials that did not allow the current to pass through are called Insulator Current is produced when a group of electrons move through a conductor SI unit of Current is Ampere Ammeter is an instrument that measures Electric current SI unit of charge is Coulomb ( equal to 6 × 10 power 18 electrons )The electric difference between the points make electrons move This difference is called Potential differenceIt is measure by an instrument called VoltmeterGood conductors have: current moves easily, low resistance, conserves energy-easy for electrons to move. Hence, Option (C) is correct.
What is conductor?Materials that easily permit the flow of electricity are referred to be electrical conductors. Conductivity is the quality of conductors that enables them to conduct electricity.
Electric current is the name given to the movement of electrons through conductor. Voltage is the amount of power necessary to cause that current to flow through the conductor.
Such an element receives a charge that is dispersed along its entire surface, causing the electrons inside the element to migrate. Charges are transferred to an electrical conductor, and they disperse until the minimal force of repulsion between electrons in locations of excess electrons. Such an item transfers its charge to another conductor when it comes into contact with it, reducing the overall repulsion caused by charge in the process.
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Who won Miami Dolphins or Las Vegas raiders
Answer:
miami dolphins.
Explanation:
......
Answer:
miami :(
Explanation:
1. If a 4000 kg rocket reaches 7,000 m/s in 8 minutes after blastoff, what is its acceleration?
2. What force is being applied to the rocket?
3. What is the rocket's potential energy when it is 12 km off the ground?
(Hint - Change kilometers to meters)
4. If the rocket were to fall from the 12 km height, what would be its speed right before hitting the ground? (assume no air resistance)
+ answer all the questions plz
Answer:
I guess the Ans for second one is gravitational force
The voltage between two points in a circuit is 3.6 V. If the resistance between
the points is 75 , what is the current, according to Ohm's law?
A. 76.6 A
B. 0.048 A
C. 20.8 A
D. 270 A
Correct answer is B!
Considering the Ohm's law, the correct answer is option B. the current is 0.048 A.
Definition of currentThe flow of electricity through an object, such as a wire, is known as current (I). Its unit of measure is amps (A). So the current is a measure of the speed at which the charge passes a given reference point in a specified direction.
Definition of voltageThe driving force (electrical pressure) behind the flow of a current is known as voltage and is measured in volts (V) (voltage can also be referred to as the potential difference or electromotive force). That is, voltage is a measure of the work required to move a charge from one point to another.
Definition of resistanceResistance (R) is the difficulty that a circuit opposes to the flow of a current and it is measured in ohms (Ω).
Ohm's lawOhm's law establishes the relationship between current, voltage, and resistance in an electrical circuit.
This law establishes that the intensity of the current that passes through a circuit is directly proportional to the voltage of the same and inversely proportional to the resistance that it presents.
Mathematically, Ohm's law is expressed as:
[tex]I=\frac{V}{R}[/tex]
Where I is the current measured in amps (A), V the voltage measured in volts (V); and R the resistance that is measured in ohms (Ω).
This caseIn this case, you know that the voltage between two points in a circuit is 3.6 V and the resistance between the points is 75 Ω.
Replacing in the Ohm's Law:
[tex]I=\frac{3.6 volts}{75 ohm}[/tex]
Solving:
I= 0.048 amps
Finally, the correct answer is option B. the current is 0.048 A.
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help please Derive an equation
Ta=1.44T1/2
Explanation:
To derive an equation you must indicate the variable you want to solve for.
Here we have tension of an object A and Tension 1.
Two variables or unknown are given hence we cannot derive any other equations.
What are stars made up of at the beginning?
Answer:
The stars were always made of hot gas a million miles away from here
Explanation:
I study stars
Consider a rigid 3-mass system ( with origin at the leftmost mass 1 kg) which can rotate about an axis perpendicular to the system. The mass are separated by rods of length 5m, so that the entire length is 10m. Find the x-coordinate of the center of the mass for the three-mass system with respect to the origin. Treat mass as particles. Answer in unit of m.
now consider a rotation axis perpendicular to the system and passing through the point Xo at distance 3.8 m from the leftmost mass 1kg. find the moment of inertia of the 3-mass system about the new axis. Answer in unit of kg.m^2
Answer:
1) x_{cm} = 5 m , 2) I = 168.32 kg m²
Explanation:
1) An important concept of center of mass is
[tex]x_{cm} = \frac{1}{M} \sum x_{i} m_{i}[/tex]
where M is the total mass of the system
Let's apply this equation to our case, suppose that all masses are equal and are worth 1 kg
[tex]x_{cm}[/tex] = ⅓ (1 0 + 1 5 + 1 10)
x_{cm} = 5 m
2) In this para indicates that there is an axis of rotation at the point xo = 3.8 m and they ask to calculate the moment inertia.
Let's use the parallel axes theorem
I = I_{cm} + M D
where I_{cm} is the moment of inertia with respect to the center of mass, D the distance between the two axes of rotation and M the total mass of the system
Let's look for the moment of inertia of the center of mass
[tex]I_{cm}[/tex] = 1 0 + 1 5² + 1 10²
I_{cm} = 125 kg m²
the total moment of inertia is
I = 125 + 3 3.8²
I = 168.32 kg m²
The moment of inertia of the 3-mass system about the new axis is 54.32 kgm/s².
We have three masses each of mass = 1kg such that they are in line with mass m at origin, m at 5m and m at 10m
(a) The center of mass:
[tex]X=\frac{m_1x_1+m_2x_2+m_3x_3}{m_1+m_2+m_3} \\ \\ X =\frac{ 1*0+1*5+1*10}{1+1+1}\\ \\ X = 5m[/tex]
Hence the center of mass of the system is at x = 5m.
(b) The moment of inertia about the axis passing through x = 3.8m
from the parallel axis theorem:
[tex]I = I_{cm} + Md^2[/tex]
where, [tex]I_{cm}[/tex] is the moment of inertial along an axis passing through the center of mass of the system, M is the total mass of the system and d is the distance of the given axis from center of mass.
M = 3kg
d = 5 - 3.8 = 1.2m
[tex]I_{cm}=1*5^2+1*0+1*5^2\\\\ I_{cm}=50 kgm/s^2[/tex]
Md² = 3×(1.2)²
Md² = 4.32 kgm/s²
I = 50 + 4.32
I = 54.32 kgm/s² is the moment of inertial about the given axis.
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Two masses 1.2kg and 1.8kg are connected to the ends of a rod of length 2m. Find the moment of inertia about the axes, 1)going through the mid point of the rod. 2)going through the centre of mass of two masses.
Answers: 1) 3 kg m²
2) 2.88 kg m²
Explanation: Question 1
I = m(r)²+ M(r)²
I = 1.2 kg × (1 m )² +1.8 kg ×(1 m )²
∴ I = 3 kg m²
Question 2
ACCORDING TO THE DIAGRAM DRAWN FOR QUESTION 2
we have to decide where the center of gravity (G) lies and obviously it should lie somewhere near to the greater mass. (which is 1.8 kg). Since we don't know the distance from center of gravity(G) to the mass (1.8 kg) we'll take it as 'x' and solve!!
moments around 'G'
F₁ d ₁ = F₂ d ₂
12 (2-X) = 18 (X)
24 -12 X =18 X
∴ X = 0.8 m
∴ ( 2 - x ) = 1.2 m
∴ Moment of inertia (I) going through the center of mass of two masses,
⇒ I = m (r)² +M (r)²
⇒ I = 1.2 × (1.2)² + 1.8 × (0.8)²
⇒ I = 1.2 × 1.44 + 1.8 × 0.64
⇒ I = 1.728 + 1.152
⇒ ∴ I = 2.88 kg m²
∴ THE QUESTION IS SOLVED !!!
Can you help with this question please
Answer:
First answer to the first question is Two people pulling a rope with the same force in a opposite direction. The other one would be 2.72N
Explanation:
Hope this helps you :)
list at least three examples of circular motion
Answer:
When an object moves with a constant speed in a circular path, then its motion is called as Circular motion.
Examples of Uniform Circular Motion :--
The moon moves in uniform circular motion around the earth.
A stoned tied to a thread and rotated in circular motion.
An athlete running on a circular track.
A satellite revolving around Earth.
Use the following free body diagram to answer questions 8 and 9:
8. Calculate the net force acting on the cart.
A 0N
B. +60N
C -60N
D. +240 N
9. Calculate the cart's rate of acceleration
A +60 m/s
B. +8 m/s
C.-2m/s
D. +2 m/s
Answer:
8 is c and 9 is b it is shown though the practice as god lol
Question 8
The net force acting on the cart is:
F = 150 N - 90 N
F = 60 N
Question 9
By the Newtons second law:
F = ma
Solving for a:
a = F/m
a = 60 N / 30 kg
a = 2 m/s²
Why did scientist struggle for thousands of years to accurately describe the solar system
Answer: C- The planets appeared to move backward in the sky occasionally.
A PERSON GETTING OUT OF MOVING BUS FALLS IN THE DIRECTION OF MOTION OF THE BUS. WHY?
Answer:
PLEASE MARK AS BRAINLIEST!!
Explanation:
A getting passenger getting down from a moving bus, falls in the direction of the motion of the bus. This is because his feet come to rest on touching the ground and the remaining body continues to move due to inertia of motion.
Answer:
When the person steps on the ground, his feet do not move but his upper body moves in the direction of the bus due to inertia of its motion. Since his upper body moves in the forward direction and his lower body does not move, the person falls in the forward direction.
2.14x10^-7. What is the answer. Write in standered form
What's a Weber?
in electromagnetism
Answer:
In physics, the weber is the SI derived unit of magnetic flux. A flux density of one Wb/m2 (one weber per square metre) is one tesla.
Hope it helps !
Answer:
Weber unit of magnetic flux in the international system of units (SI), defined as the amount flux that, linking an electrical circuit of one turn (one loop of wire) , produces in it an electromotive force of one volt as the flux is reduced to zero as a uniform rate in one second .
it was named in honour of the 19th century German physicist Wilhelm Eduard Weber
what is a atomic nuclues
Use the following information to answer questions 4 and 5:
A rock is launched vertically into the air at a velocity of 14.75 m/s.
4. Toby claims that the rock must come to rest before it can fall back towards the ground. Is Toby
correct?
A. Toby is correct because the rock is experiencing a negative acceleration, causing its negative
velocity to increase until the rock reaches a velocity of O m/s before becoming positive.
B. Toby is correct because the rock is experiencing a negative acceleration, causing its positive
velocity to decrease until the rock reaches a velocity of O m/s before becoming negative.
C. Toby is incorrect because the rock is experiencing a positive acceleration, causing its positive
velocity to increase in magnitude.
D. Toby is incorrect because the rock is experiencing a negative acceleration, causing its positive
velocity to increase in magnitude.
5. Calculate the time it takes for the rock to reach its maximum height.
A. 1.50 seconds
B. 2.47 seconds
C. 3.00 seconds
D. 4.94 seconds
Question 4
B. Toby is correct because the rock is experiencing a negative acceleration, causing its positive velocity to decrease until the rock reaches a velocity of O m/s before becoming negative.
Question 5
At the maximum height, velocity is 0, so:
v = v₀ - gt
0 = 14.75 - 9.8t
t = 14.75/9.8
t = 1.5 s (OPTION A)
4). In the given situation, the assertion that could be made regarding Toby would be:
B). Toby is correct because the rock is experiencing a negative acceleration, causing its positive velocity to decrease until the rock reaches a velocity of O m/s before becoming negative.
5). The time that would be taken by the rock to attain its greatest height would be:
1.5 second
4). Tobby correctly states as rock would be undergoing a -ve acceleration which leads its +ve velocity to fall by the time rock attains the velocity of 0 m/s.
Thus, option B is the correct answer.
5). Given that,
Initial velocity([tex]v_{0}[/tex]) = 14.75 m/s
As we know,
Velocity remains 0 m/s at the greatest height,
So,
Velocity(v) [tex]= v_{0} - gt[/tex]
where
[tex]0 = 14.75 - 9.8t[/tex]
⇒ [tex]t = 14.75/9.8[/tex]
∵ [tex]t = 1.5 s[/tex]
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What is the water cycle ?
Answer:
The water cycle shows the continuous movement of water within the Earth and atmosphere. ... Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow. Water in different phases moves through the atmosphere (transportation).
Explanation:
It's the water cycle.
Explain
applications
MRI
X-ray
Ultrasound
Infrared Radiation
Answer and Explanation:
--> MRI (Magnetic Resonance Imaging) is an imaging technique that involves the use of radio waves and magnetic field to generate high detailed images of the human body. It's clinical applications includes:
• Bone and joint MRI: these are done to check for bone and joint problems such as bone marrow disorders, arthritis, or bone tumours.
• A Spine MRI: This is used to investigate the spinal disc and innervations for disorders such as spinal tumours.
• Chest MRI: This is used to detect abnormalities of the heart, heart valves and coronary arteries.
--> X-RAY: These are electromagnetic waves of short wavelength with high penetrating power. They are produced when fast moving electrons strike a mass of heavy atoms such as those of metals. It's applications includes:
• They are used to detect hidden cracks in materials.
• They are used to show broken bones in human body.
• They are used in the study of internal structures of crystals.
• In agriculture, x-rays are used in killing germs.
--> ULTRASOUND: This makes use of high frequency sounds to detect abnormalities in the human body. An ultrasound machine transmits sound waves into the body which are reflected at the surfaces between the tissues of different density. It can also be used in different disciplines such as imaging, cleaning, mixing, navigation and communication It's applications includes:
•. Detection of Cracks: when applied on metallic surface under investigation, high frequency sound wave reflects back which and be predicted and recorded.
--> INFRARED RADIATION: This is a type of electromagnetic radiation with wavelength longer than visible light. It is visible to the human eye and most heated surfaces transmits infrared radiation. It's applications includes:
• it is used for the purpose of sensing and detection. For example the night vision goggles and infrared cameras. Remote control makes use of infrared light waves to change channels in the television.
If a sinusoidal electromagnetic wave with intensity 18 W/m2 has an electric field of amplitude E, then a 36 W/m2 wave of the same wavelength will have an electric field of amplitude?
a. 4E
b. 2 underroot 2E
c. 2E
d. underroot E
Answer:
The correct option is D
Explanation:
From the question we are told that
The intensity of the first electromagnetic wave is [tex]I = 18 \ W/m^2[/tex]
The amplitude of the electric field is [tex]E_{max}_1 =A[/tex]
The intensity of the second electromagnetic wave is [tex]I = 36 \ W/m^2[/tex]
Generally the an electromagnetic wave intensity is mathematically represented as
[tex]I = \frac{1}{2} * \epsilon_o * c * E_{max}^2[/tex]
Looking at this equation we see that
[tex]I \ \ \alpha \ \ E^2_{max}[/tex]
=> [tex]\frac{I_1}{I_2} = [ \frac{ E_{max}_1}{ E_{max}_2} ] ^2[/tex]
=> [tex]E_{max}_2 = \sqrt{\frac{x}{y} } * E_{max}_1[/tex]
=> [tex]E_{max}_2 = \sqrt{\frac{36}{18} } * E[/tex]
=> [tex]E_{max}_2 = \sqrt{2 } E[/tex]
A 100 kg gymnast comes to a stop after tumbling. Her feet do 5,000 J of work to stop her.
Which of the following was the girl's velocity when she began to stop?
Answer:10 m/s
Explanation:
A 100 kg gymnast comes to a stop after tumbling. Her feet do 5,000 J of work to stop her. The girl's velocity when she began to stop is 10 m/sec.
What is velocity?When an item is moving, its velocity is the rate at which its direction is changing as seen from a certain point of view and as measured by a specific unit of time. Velocity is vector quantity.
Uniform motion an object is said to have uniform motion when object cover equal distance in equal interval of time within exact fixed direction. For a body in uniform motion, the magnitude of its velocity remains constant over time. Here in the question velocity is changing by using work energy theorem we have,
work done = change in kinetic energy
5000 = (.5).m.v² , where v is velocity.
5000 = (.5).100.v²
v = 10 m/sec
A 100 kg gymnast comes to a stop after tumbling. Her feet do 5,000 J of work to stop her. The girl's velocity when she began to stop is 10 m/sec.
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A street bridge is 5.5m long if the linear expansion of steel is 0.00001 oc How much will it expand when temperatures is by 10oc? Give answer in Cm
Answer:
[tex]l_o=550.055\ cm[/tex]
Explanation:
Given that,
Length of a street bridge, l = 5.5 m
The coefficient of bridge, [tex]\alpha =0.00001 ^0 C[/tex]
We need to find how much will it expand when temperatures is by 10°C.
The change in length per unit original length is given by :
[tex]\dfrac{\Delta l}{l}=\alpha \Delta T\\\\\Delta l = l\alpha \Delta T\\\\=5.5\times 0.00001 \times 10\\\\\Delta l=0.00055\\\\(l_o-l)=0.00055\\\\l_o=0.00055+5.5\\\\=5.50055\ m\\\\l_o=550.055\ cm[/tex]
Hence, the length will expanded 550.055 cm.