If the braking force is 10000 N, 90 meters is far the car travel before stopping.
What is force ?When an object interacts with another object, it experiences a push or pull known as a force. Every time two objects come into contact, a force is applied to each one of them. Actual forces can only be created by interaction.
What is energy ?The definition of energy is "the ability to do work, which is the capability to apply a force causing the displacement of an object." Despite this vague description, energy simply refers to the power that propels motion.
Given that,
Mass of automobile = 2000 kg
speed = 30 m/s
Braking force = 10000 N
For, The acceleration is
Using newton's formula
Where, f = force
m= mass
a = acceleration
Put the value of F and m into the formula
-10000 = 2000*a
The braking force is visible in the negative sing.
It demonstrates that the force's direction is the inverse of the motion.
a = -10000/2000
a = -5m/s2
For the distance,
Using third equation of motion
[tex]v^{2} - u^{2} = 2as[/tex]
[tex]0- 30^{2} = 2 * (-5) *s[/tex]
s = 90m
Consequently, the automobile went 90 meters before coming to a stop.
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When distances were carefully measured from the Earth to globular clusters above and below the Milky Way plane (where our view of them is not obscured by interstellar dust and gas), their distribution was found to be
A) spherically symmetric about a point in the constellation Sagittarius and concentrated in that direction.
B) in a relatively flat disk almost perpendicular to the plane of the Galaxy, with a relatively higher density of clusters toward its center.
C) concentrated in the plane of the Milky Way and clustered around the Sun's position, indicating that the Sun is close to the Galaxy's center.
D) uniformly distributed throughout space, with no concentration in any area of the Milky Way.
Answer:
A) Spherically symmetric about a point in the constellation Sagittarius and concentrated in that direction
Explanation:
The globular clusters are present mainly in the direction of Sagittarius with the center of the system of globular cluster being measured as a spherical cluster cloud such that the center of the Milky Way can be taken as being in the Sagittarius constellation
A student investigates the effect of a crumple zone on the force exerted during a collision The student has one trolley with a spring at the front and another trolley without a spring
silver foil
spring
silver foil
trolley
The student uses the arrangement in Figure 10.
trolley
silver foil
ramp
trolley
silver foil
rigid wall
too
Figure 10
000 ms
millisecond timer
After a trolley is released, it accelerates down a slope and bounces off a rigid wall
The speed of a trolley can be measured just before a collision with the wall and just after a collision with the wall.
The silver foils are connected to a millisecond timer.
The silver foils make contact with each other during the collision, so the time they are in contact can be read from the millisecond timer.
Explain how the student could investigate the effect of a crumple zone on the average force exerted during the collision.
Your explanation should include:
how to determine the force (you may wish to refer to an equation) how the effect of crumple zones may be shown in the investigation precautions that may be necessary to achieve accurate results.
(6)
The impulse allows to calculate which material is better to reduce the damage in a crash are:
Measure the speeds, time and calculate the force for each deformation, with the relationship.The best deformation zone is the one that gives the least force. Some care must be taken.* The most important is that the system starts from the same point so that the speed before the crash is always the same.
* The second is that the mass of the car plus the training materials is always the same.
* Check the zero and streamline of the equipment before measurements.
The student can use the relationship between impulse and momentum variation.
I = ∫ F dt = Δp
Where I is the momentum, F the force, t the time and Δp the variation of the momentum.
The momentum is defined by the product of the mass of the vehicle and the speed.
p = m v
Where m is the mass and v the velocity.
Since you want the average force, you can take the force out of the integral.
F t = m v_f -m v₀
They indicate that the system can measure the speed just before and after the collision with the wall, it is also capable of measuring the time of the collision, therefore we can calculate the force with the expression.
[tex]F = m \ \frac{v_f - v_o}{t}[/tex]
therefore the student can calculate the force for each type of deformation zone. The best deformation zone is the one that gives the least force.
Several cautions must be taken in the experiment:
* Exit from the same point each time.
* Keep the mass constant for the whole experiment, for this, care must be taken with the different weights of each material.
* Check that the equipment is properly calibrated and reset to zero before starting each measurement.
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Re word this paragraph; so Its 'put in my own words' try to mix up the places of each sentences too please!
-
The sun creates three different types of electromagnetic radiation, which is considered harmful to humans. The light created includes X-rays, gamma rays, and ultraviolet light. These rays are harmful because of their high energy values, which are caused by their large frequencies. The gases of Earth's atmosphere absorb the high energy radiation, causing their molecules to move faster, but none of the light radiation reaches Earth's surface. Luckily for us, the high frequency of gamma rays and X-rays, as well as most ultraviolet light, cannot penetrate Earth's atmosphere and does not reach Earth's surface. If those harmful rays did reach Earth's surface it would make the planet plain to earth's
-
Answer:
here you go -
Explanation:
try using the paraphrasing tool website!
The sun makes three unique sorts of electromagnetic radiation, which is considered hurtful to people. The light made incorporates X-beams, gamma beams, and bright light. These beams are unsafe as a result of their high energy esteems, which are brought about by their enormous frequencies. The gases of Earth's air assimilate the high energy radiation, making their atoms move quicker, yet none of the light radiation arrives at Earth's surface. Fortunately for us, the high recurrence of gamma beams and X-beams, also as most bright light, can't enter Earth's environment and doesn't arrive at Earth's surface. In the event that those hurtful beams arrived at Earth's surface it would make the planet plain to earth's
How much work is done by gravity to cause a 12.0 kg stone to drop from a height of 22.0 m to a height of 3.00 m?
Answer:
Work done is 2280 Joules.
Explanation:
Work done can be found using the formula
[tex]W=Fs\\[/tex]
where:
W is work done ( in Joules)
F is force ( in Newtons)
s is displacement ( in Meters)
Assuming we are on Earth, we can find the force acting on the object using the mass with the following:
Mass × 10 = Force
12.0 × 10 = 120N
Moreover, we can find displacement by simply subtracting the final distance from the starting distance:
22.0m - 3.00m = 19.0m
Therefore,
[tex]W = Fs[/tex]
[tex]W = 120N[/tex] × [tex]19m[/tex]
[tex]W= 2280J[/tex]
The impulse that the pelton wheel applies to the water is ___ the change in momentum of the water after hitting the flat paddle wheel?
The impulse that the pelton wheel applies to the water is equal to the change in momentum of the water after hitting the flat paddle wheel.
What is the pelton wheel about?Impulse is a measure of the force applied to an object over a period of time, and it is equal to the change in momentum of the object.
In the case of the pelton wheel, the force is applied to the water by the flat paddle wheel, and the change in momentum of the water is the result of that force.
Therefore, The impulse of the pelton wheel is therefore equal to the change in momentum of the water after it hits the paddle wheel.
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What is a pivot arm lever?
The forearm serves as the lever arm, while the elbow serves as the pivot. In spite of the forearm's weight and whatever additional weight the hand may be bearing, the biceps muscle exerts the force and bends the forearm. Compared to the effort, the weight is further from the pivot.
A moving bar that pivots on a fulcrum fastened to a fixed point is the lever. The lever works by exerting forces at various angles in relation to the pivot or fulcrum. Ones farther from this pivot move more quickly than points closer to it when the lever revolves around the fulcrum.
A moving bar that pivots on a fulcrum fastened to a fixed point is the lever. The lever works by exerting forces at various angles in relation to the pivot or fulcrum. Ones farther from this pivot move more quickly than points closer to it when the lever revolves around the fulcrum.
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In some situations, matter demonstrates wave behavior rather than particle
behavior. This is best illustrated by which phenomenon?
A. Photoelectric effect
B. Emission spectra of atoms
О
C. Blackbody radiation
D. Interference patterns of electrons
Answer:
D. Interference patterns of electrons
Explanation:
How should two resistors, with resistances R1 Ω, R2 Ω, be connected to a battery of
e.m.f. V volts so that the electrical power consumed is minimum?
Answer:
The two resistors should be connected in series.
(I assume that the question is stating the electrical power consumed by the resistors)
Explanation:
Think about the formula P = V^2 / R
For the electrical power consumed to be a minimum, we must let V be as small as possible.
For small V, between a series and a parallel connection, series is the correct connection as the combined potential difference (pd) for the two resistors is equal to the electromotive force (emf) of the battery.
However, for parallel connections, the combined pd for the two resistors is equal to twice the emf of the battery. (Each resistor will have a pd equal to the emf of the battery)
With lower total V, with the same R, power P consumed will decrease.
People who r good at physics pls help...
In your own words, describe the difference between velocity and speed and how they relate to distance and displacement.
*IF YOU POST LINKS I WILL REPORT YOU*
Answer:
Speed and velocity both measure an object’s rate of motion. However, speed is a scalar quantity, which means that it can be described with a numerical value. Velocity is a vector quantity, which depends on direction as well as magnitude. Read these definition for more information:
speed - the rate of distance traveled by a moving object over time
velocity - the rate of displacement of a moving object over time
Basically, an object’s speed tells you how fast it’s going. Its velocity tells you how fast it’s going in a certain direction. You use speed measurements in your daily life, but physicists depend on velocity measurements more frequently in their work.
Explanation:
If the separation is decreased to 1.90 mm , what is the energy now stored if the capacitor was disconnected from the potential source before the separation of the plates was changed
When the distance between the plates is decreased to 1.90 mm, the capacitance of the capacitor will increase and the energy stored in the capacitor will also increase.
However, since the voltage across the plates is not given, it is not possible to calculate the energy stored in the capacitor after the separation of the plates has been changed
The below equation gives the capacitance of a parallel-plate capacitor.
C = ε * A / d
Where ε is the dielectric constant of the material between the plates, A is the area of the plates and d is the distance between the plates.
The energy stored in a capacitor is given by the equation:
Energy = 1/2 * C * V^2
where V is the voltage across the plates and C is the capacitance
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Sam is standing close to two speakers that are playing music at a party, but when a single note is held for a long time, it seems very soft to him. Why?
When a single note is kept for a long time, it seems very soft to him. This is because he is standing at a point where the rarefactions of the sound wave from one speaker meet the compressions of the sound wave from the other speaker.
A longitudinal wave propagates by means of compressions and rarefactions. When a vibrating object motions forward, it shoves and compresses the air in a veneer of it building a region of high pressure. When a sound wave travels through a medium, say air, the particles of the medium disturb in the same fashion, i.e. compression and rarefaction. Compression is illustrated for the longitudinal waves in which the particles come nearer such that it is at high pressure.
Rarefaction is specified for the longitudinal waves in which the particles move apart such that it has low pressure.
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true or false Visual inspection of the brake drum friction surface is not required, only measure drum diameter.
It is False that Visual inspection of the brake drum friction surface is not required, only measure drum diameter.
What serves as a brake drum?No matter whether the vehicle is moving forward or backward, drum brakes produce uniform braking force. Drum brakes produce the same amount of braking force in both directions, which explains this. This kind is typically utilized for the passenger car's rear brakes.
Unusual brake pedal sensation is one of the first indications when drum brakes are damaged or failing. Excessive brake drum wear might result in vibrations that can be felt in the pedal. When you press the pedal, any trembling or pulsating brought on by worn drums will be audible.
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Twice each lunar month, all year long, these tides occur. Whenever the moon, earth, and sun are aligned, the gravitational pull of the sun ___ to that of the moon causing ___ tides.
A. Adds ; neap
B. Adds ; maximum
C. Interferes ; neap
D. Interferes ; minimum
i need the answer now so just the answer and not a long explanation would be great ! thanks !
These tides occur twice each lunar month throughout the entire year. When the earth, moon, and sun are all in alignment, neap tides are produced by the sun's gravitational pull amplifying that of the moon.
When the sun and moon are both on the same side of the Earth, what tides occur twice a month?Instead, the phrase refers to the idea of the tide "springing forth." Regardless of the season, spring tides happen twice each lunar month. Neap tides happen when the sun and moon are at right angles to one another, which also happens twice a month.
What are the names of moon tides?The sun, the form of the ocean, and the moon all have an impact on how much or little the tide rises or falls on Earth. Moon tides are the results of the moon's influence on the Earth's tides. The major subject of this article is moon tides.
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Which of the following is a thermodynamic process in which a system returns to the same conditions under which it started?
A) a cyclic process
B) an adiabatic process
C) an isovolumetric process
D) an isothermal process
A cyclic process is a thermodynamic process where the initial and final states are identical. As a result, both the system's initial and end internal energies are constant. As a result, the system's capacity to absorb heat is determined by the work it performs during a cycle.
What is a Thermodynamic Process?A thermodynamic process is one that modifies the system's thermodynamic state. A transition from an initial to a final state of thermodynamic equilibrium characterizes a change in a system. The actual course of the process is not the main focus in classical thermodynamics and is frequently disregarded.
There are several different types of thermodynamic processes, such as (a) isothermal, in which the system's temperature stays constant; (b) adiabatic, in which no heat is exchanged; (c) isobaric, in which the system's pressure stays constant; and (d) isochoric, in which the system's volume stays constant.
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Waves are caused by which energy
Answer:
Waves are most commonly caused by wind.
Explanation:
Waves are most commonly caused by wind. Wind-driven waves, or surface waves, are created by the friction between wind and surface water. As wind blows across the surface of the ocean or a lake, the continual disturbance creates a wave crest.
Daniel and Christopher were on a plane traveling at a velocity of 200 km/hr south for 1,000 km. How long (in hours) was the plane flying at that velocity?
A grocery shopper tosses a(n) 9.0 kg bag of rice into a stationary 19.1 kg grocery cart. The bag hits the cart with a horizontal speed of 6.7 m/s toward the front of the cart. What is the final speed of the cart and bag
The speed with which the cart and bag move after the collision is equal to 2.14 m/s.
Given the following data:
Mass of bag = 9.0 kg
Speed of bag = 6.7 m/s
Mass of cart = 19.1 kg
Speed of cart = 0 m/s (since it is initially at rest or stationary).
To calculate the final speed with which the cart and bag move after the collision:
Applying the law of conservation of momentum, the collision between the cart and bag is given by the formula:
Where:
M is the mass.
V is the velocity.
Substituting the given parameters into the formula, we have;
9.0 × 6.7 + 19.1 × 0 = Vf (9+19.1)
60.3 = vf (28.1)
vf = 60.3/28.1
vf = 2.14 m / s
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What is the difference between dynamic and active stretching?
Stretching that is passive, such as static stretching, is contrasted with active stretching, such as dynamic stretching. It entails motion, putting the muscles and joints through their full range of motion.
Are dynamic active stretches the same?Active stretching – what is it? Active stretching is the process of relaxing and stretching opposing muscles without the use of external pressures, as opposed to dynamic stretching or ballistic stretching. Stretching that is active is not passive.
What are a few instances of stretching actively?In general, an active stretch doesn't require the use of an external force. An illustration would be a side-leaning stretch with the arms overhead. It is not necessary to pull, push, hold, brace, or hold the stretch. Active stretching is a common practice in yoga, as you'll discover.
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What is the Hairdryer energy transfers
Answer:
it transfers heat to the hair to make it dry with the hot air which would be thermal energy
Based on the age of the light- and dark-colored regions of the Moon and the number of craters observed in these regions, we know that impacts in the inner Solar System:
Based on the age of the light- and dark-colored regions of the Moon and the number of craters observed in these regions, we know that impacts in the inner Solar System rapidly decreased approximately 3 billion years ago.
The light-colored areas of the Moon's surface are roughly 1 billion years older than the dark-colored regions.
The dark patches are basalt-based juvenile plains known as maria. The basalt poured in and inundated the region left by a massive asteroid or comet collision. The bright regions are the highlands, which are raised mountains caused by impacts.
The light-colored material is found in portions of the Moon known as the highlands, which represent the Moon's oldest crust.
The lunar highlands are the earliest lunar features. This is mostly determined by the amount of impact craters found in various locations of the moon.
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In the sketch to the right, a long straight wire is in the plane of a rectangular conducting wire loop. The current in the straight wire is up. At some point the current in the straight wire starts to increase in magnitude. This increased current leads to an induced current in the wire loop. In which direction will the induced current in the wire loop be? Explain how you reached this conclusion. How would your answer be different if the wire loop was on the left side of the wire instead of the right side?
The direction of the induced current in the wire loop is anti-clockwise.
The direction of the induced current if the wire loop was on the left side of the wire is clockwise.
Lenz's law and the direction of the induced current are the key concepts needed to address this issue.
To determine the direction of the induced current under various circumstances, use Lenz's law.
The induced emf of the coil is proportional to the negative of the rate of change of magnetic flux, according to Faraday's law.
The following expression represents the typical emf that is generated in the coil during the course of the time period: [tex]$$\varepsilon=-\frac{\Delta \Phi}{\Delta t}$$[/tex]
Here, [tex]$\varepsilon$[/tex] is the average emf that is induced in the coil during the time interval and [tex]$\Delta \Phi / \Delta t$[/tex] is the rate of change of magnetic flux.
A magnetic field is induced in the rectangular loop as a result of the current in the wire. The plane is the intended target of this magnetic field.
As the current in the wire grows, the magnetic flux in the rectangular coil rises.
An emf and current are induced by Faraday's law.
Following is noted from Lenz's law:
The inwards growing flux is opposed by the generated current. Therefore, the induced current must flow counterclockwise in order to meet this.
When the rectangular loop is kept to the left of the wire, the magnetic flux will be directed outward.
If the wire loop was on the left side of the wire, the induced current would flow clockwise.
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A 55 kg skater pushed by a friend accelerates 3 m/s2. How much force did the friend apply?
Answer: 165 N.
Explanation: To find out how much force was applied by the friend, you need to use the following formula:
F = ma where F is force, m is mass, and a is acceleration. Now we can plug in the values given.
F = 55 x 3 = 165
F = 165
The amount of force the friend applied is 165 N.
Hope this helps! :)
A photon is ___________________. a type of wave a form of kinetic energy a quantum of light an electrostatic force
The photon is typically described as an electromagnetic (EM) wave, such as the image below. These are the two components of the wave longitudinal and transverse.
What is a photon?A photon is a particle of light which essentially is a packet of electromagnetic radiation. The energy of the photon depends on its frequency (how fast the electric field and magnetic field wiggle, this needs better wording, for 'fast electric field' and 'wiggle'.
What is a photon made of?A photon is a tiny particle that comprises waves of electromagnetic radiation. As shown by Maxwell, photons are just electric fields traveling through space. Photons have no charge, no resting mass, and travel at the speed of light.
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A billiard ball moves with 5 kg⋅m/s of momentum and strikes three other billiard balls. What is the total momentum of the balls after the collision?
3 kg⋅m/s
4 kg⋅m/s
5 kg⋅m/s
6 kg⋅m/s
The momentum of the billiard balls after the collision is 3 Kgm/s.
What is Momentum?Simply multiplying the mass of an object by its velocity results in momentum. Additionally, because momentum has both magnitude and direction, it qualifies as a vector quantity.
The formula provides momentum in mathematics;
The other pool balls' velocities would be zero (0) m/s because they were at rest (not experiencing any motion). If we substitute the values, we get: Total forward motion is 3 kg/s.
As a result, the billiard balls' post-collision momentum is 3 Kgm/s.
Therefore, The momentum of the billiard balls after the collision is 3 Kgm/s.
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a danger to a driver of not wearing a safety belt during a sudden stop
Explanation:
When you brake all of a sudden, if you are not wearing a seat belt, your face is bound to hit against the windshield. The seat belt stops this inertia. If your car is going at 60 MPH, your face will be saved from the impact. ... There are many accidents where the driver is thrown out of the car and this can be deadly.
a runner runs around a circular track covers a distance of 200m, ending in the spot where she started if the entire trip takes 50 seconds , what is her average velocity?
Answer:
0 ms-1
Explanation:
This is a trick question.
* Don't be confused with average speed with average velocity
Since the runner ends in the same spot as she started,
the total displacement covered by the runner is zero.
Since average velocity = total displacement/total time,
As total displacement is zero ,
average velocity = 0 / 50 ms-1
= 0 ms-1
If 10.0 g of water is initially heated from 20°C to 100°C, and then it is continually heated through its phase change (it is vaporised), what is the total amount of energy necessary to carry out this process?
Answer:
The total amount of energy necessary to carry out this process is 22600 joules (J).
Explanation:
This is because the heat of vaporization (the energy required to change the state of water from liquid to gas) of water is 2260 J/g. Since 10.0 g of water is being heated, the total amount of energy needed is 10.0 g * 2260 J/g = 22600 J.
1. An interstellar spacecraft, far from the influence of any stars or planets, is moving at high speed under the influence of fusion rockets when the engines malfunction and stop. The spacecraft will (A) immediately stop, throwing all of the occupants to the front of the craft. (B) begin slowing down, eventually coming to a rest in the cold emptiness of space. (C) keep moving at constant speed for a while, but then begin to slow down. (D) keep moving forever at the same speed.
Using Newton's 1st law of motion. In the absence of external force, the isolated object maintains its condition of uniform motion. Thus, the spaceship keeps its constant speed throughout all of time. Option D is correct.
Newton's First Law: InertiaAccording to Newton's first law, unless pushed to alter its condition by the operation of an external force, every object will continue to be at rest or even in uniform motion along a straight line. Inertia is the propensity to maintain balance in a condition of motion.
What does it mean to be inert?The word "inertia" is derived from the Latin word iners, which meaning idle or sluggish. Inertia is the name for any physical object's opposition to a velocity change. Changes in the item's motion's direction or speed fall under this category.
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The aorta is a major artery, rising upward from the left ventricle of the heart and curving down to carry blood to the abdomen and lower half of the body. The curved artery can be approximated as a semicircular arch whose diameter is 4.1 cm. If blood flows through the aortic arch at a speed of 0.30 m/s, what is the magnitude (in m/s2) of the blood's centripetal acceleration
The centripetal acceleration of the aorta in which the blood travels with the speed of 0.30 m/s is 2.2 m/s²
The diameter of the aorta = 4.1 cm
= 4.1 x 10⁻² m
The speed of the blood through the aorta = 0.3 m/s
The centripetal acceleration of the blood passing through the aorta can be found using the formula,
a = v²/r
where a is the centripetal acceleration
v is the speed of the blood passing through the aorta
r is the diameter of the aorta
Let us substitute the known values in the above equation, we get
a = 0.30² / (4.1 x 10⁻²)
= 0.09 / (4.1 x 10⁻²)
= 0.022 x 10²
= 2.2 m/s²
Therefore, the centripetal acceleration of the aorta is 2.2 m/s²
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The Humber Bridge in England has the world's longest single span, 1410 m. Calculate the change in length of the steel deck of the span when the temperature increases from -5.0 degree C to 18.0 degree C.
Assuming the steel deck has a coefficient of linear thermal expansion of 12 x 10-6 m/m/°C, the change in length of the steel deck of the span when the temperature increases from -5.0 degree C to 18.0 degree C is 2.16 m. (1410 m x 12 x 10-6 m/m/°C x 23°C = 2.16 m)
Steel is an alloy made of iron and other elements, and is one of the most widely used materials in the world. Steel structures such as bridges are subject to changes in size and shape due to changes in temperature. When steel is exposed to temperatures higher than 0°C, it expands, and when it is exposed to temperatures lower than 0°C, it contracts.
The coefficient of linear thermal expansion is the rate at which the length of an object changes with temperature. This coefficient can vary depending on the type of steel and other factors. For the Humber Bridge, the steel deck of the span has a coefficient of linear thermal expansion of 12 x 10-6 m/m/°C. Therefore, when the temperature increases from -5.0°C to 18.0°C, the steel deck of the span will expand by 2.16 m.
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