The idea that light consists of photons, bundles of pure energy, was first proposed by?

Cascading style sheet(CSS) rules are comprised of  selectors and declarations.

When describing the display of a document published in a markup language like HTML or XML, Cascading Style Sheets (CSS) is the language utilized (including XML dialects such as SVG, MathML or XHTML). Along with JavaScript and HTML, CSS is a key component of the World Wide Web. Layout, color, and font customization are all possible with CSS, which is made to separate display from content. By defining the pertinent CSS in a separate file, this separation can make content more accessible, give definition of presentation characteristics more freedom and control, and allow numerous web pages to share formatting.

To learn more about Cascading style sheet, visit:

https://brainly.com/question/14122880

#SPJ4

Friction is a force caused by the contact of one surface on another: a. true

The Friction force is the force that opposes the displacement of an object or body on a contact surface. The greater the opposition the contact surface exerts on the displacement of an object, the greater the frictional force.

The general formula for the friction force is:

Fr = μ * N * Uv

Where:

It is the physical magnitude that expresses the effort necessary to move the mass of one kilogram with an acceleration of one meter per second squared, this is expressed in units of the international system in Newton.

Learn more about force at: brainly.com/question/12970081

#SPJ4

According to Stefan’s law, a hotter body radiates 68 times more energy per unit area per second

As per Stefan’s law, Fhotter/Fcooler = 68

The Stefan law or the Stefan-Boltzmann law, states that the total radiant heat power that is emitted from a surface per unit area at the absolute temperature is directly proportional to the fourth power of its temperature.

The unit used in Stefan’s law is σ which equals to Wattm−2k−4

This law was formulated by Josef Stefan in 1879 through his experimental studies and again by Ludwig Boltzmann in 1844 from thermodynamic considerations.

To know more about Stefan’s law, visit:

https://brainly.com/question/13170634

#SPJ4

A protective layer that shields the surface from lethal ultraviolet light is found in second layer of the atmosphere i.e., stratosphere.

More about ozone

The ozone layer is a component of the stratosphere, which is the second layer of the Earth’s atmosphere. The stratosphere is the name given to the layer of insulating gases that clings to our globe.

Ozone is a trace gas since there are only around 3 of its molecules in the atmosphere for every 10 million air molecules. But it serves an important purpose.

Like a sponge, the ozone layer absorbs sunlight that reaches Earth. While some of the sun’s radiation is essential for our survival, excessive amounts can be harmful to other living things.

The ozone layer shields life on Earth.

Benefits of ozone

Ozone does a good job of trapping ultraviolet radiation, also known as UV light, which may damage DNA molecules in plants and animals and penetrate protective layers on creatures like the epidermis.

The two primary subtypes of UV light are UVB and UVA.

UVB causes skin conditions including sunburns and cancers like basal cell carcinoma and squamous cell carcinoma.

To know more about ozone visit:

https://brainly.com/question/11912585

#SPJ4

Answer:

In the Stratosphere

The protective layer is made of OZONE (O3). It shields us from the Sun's ultraviolet light. If the Ozone layer in the stratosphere becomes thin (letting more ultraviolet light through) it can lead to light and severe health effects, both to humans and animals, and can even affect food webs. In people, excess UV light can lead to certain forms of cataracts, increase in burns, cataracts, and sometimes even mutations (according to my FLVS Envornmental science course).

Have a great day!

The time needed to take off is 0.8s

Acceleration can be defined as the rate of change of velocity. It is a vector quantity.

Given that a plane accelerates from rest at a constant rate of 5.0 m/s² along a runway that is 1800 mm long. Assume that the plane reaches the required takeoff velocity at the end of the runway.

The takeoff velocity V will be

V² = U² + 2aS

Where

Substitute all the parameters into the formula above

V² = 0 + 2 × 5 × 1.8

V² = 18

V = √18

V = 4.24 m/s

The time t needed to take off will be

V = U + at

4.24 = 0 + 5t

5t = 4.24

t = 4.24 / 5

t = 0.8 s

Therefore, the time needed to take off is 0.8s

Learn more about Time here: https://brainly.com/question/10428039

#SPJ1

Given,

The magnitude of the resultant force is 39.7 N and makes an angle of 49.5° with the x-axis.

The two given forces are vectors, thus they have to be resolved horizontally and vertically to determine their resultant.

So that:

 Horizontal component = F Cos θ

  Vertical component = F Sin θ

Thus, given that: a = 28 lb at 45° on x & y axis, and b = 12 lb at 30° below x-axis.

i. Resolving the vector horizontally, we have:

horizontal component = 28 Cos 45° + 12 Cos 30°

                                    = 19.80 + 10.39

horizontal component, x  = 30.19

ii. Resolving the vectors vertically, we have:

vertical component = 28 Sin 45° + 12 Sin 30°

                               = 19.80 + 6.0

vertical component, y  = 25.80

a. Magnitude of the resultant force, |R| = [tex]\sqrt{x^{2} + y^{2} }[/tex]

= [tex]\sqrt{(30.19)^{2} +(25.80)^{2} }\\\\[/tex]

= 39.7124

|R|     = 39.7 Newtons

b. The angle that the resultant makes with the positive x-axis can be determined by:

[tex]Tan\ \theta = \frac{x}{y} \\\\\theta = Tan^{-1} \frac{30.19}{25.80} \\\\= 49.4832\\\\\theta = 49.5\textdegree[/tex]

Therefore, the magnitude of the resultant force is 39.7 N and makes an angle with the x-axis.

Learn more about resultant here:

https://brainly.com/question/19492935

#SPJ4

In a lab setting, a systematic error frequently causes high precision with low accuracy. Either the measurer consistently makes the same error, or the measuring device has a fault. Even while a badly calibrated balance might consistently read the same mass, it will be far lower than the actual mass of the object.

Accuracy is defined as "the degree to which the outcome of a measurement adheres to the correct value or a standard. basically refers to how closely a measurement fits the established value." The degree to which the outcome of a measurement complies to the proper value or a standard," is how accuracy is defined.

The more traditional term is "accuracy of measurement," which is defined as "... the degree to which the outcome of a measurement agrees with the genuine value of the thing being measured."

To learn more about accuracy, visit: https://brainly.com/question/13377944

#SPJ4

The gold sheet used was around 1000 atoms thick.

The Rutherford observed that the use of aluminium foil will be better instead of gold foil, the reason is given below. The gold is very cheap metal so due to this property it can be easily turned into thin thin foil, Rutherford wants the thinnest layer as thin as possible. If any other metal foil is used in place of gold then also there will be no change in the observations if the metal foil to be used is as thin as gold foil.

So we can conclude that the gold sheet used was around 1000 atoms thick.

Learn more about Gold Foil here: https://brainly.com/question/730256

#SPJ1

Two common stars are observed by an astronomer. It turns out that the first one is twice as hot as the second. This indicates that the first emits around 16 times as much energy as the second.

Astronomers are specialists in the field of astronomy, which is the study of celestial bodies and phenomena. They use various methods to explore and understand space beyond Earth, including using telescopes, satellites, and mathematical models.

They also compile data on different astronomical objects into comprehensive databases that can be used by researchers all over the world. This helps us to better understand our universe and how it works. Additionally, astronomers work towards developing new technologies that will help us probe further into space. As we continue to learn more about our galaxy and its many inhabitants, astronomers have a significant role to play in informing society about these discoveries.

To learn more about Astronomers, visit:

https://brainly.com/question/16471213

#SPJ4

According to the given statement the value of :

a -  [tex]\overrightarrow{\mathrm{A}}=\mathrm{A}_{\mathrm{x}} \hat{\mathrm{i}}+\mathrm{A}_{\mathrm{y}} \hat{\mathrm{j}}=-3.00 \hat{\mathrm{i}}+2.00 \hat{\mathrm{j}}[/tex]

b - θ is in the second quadrant so θ = 180⁰ + (-33.7⁰) = 146⁰

c-[tex]\overrightarrow{\mathrm{B}}=3.00 \hat{\mathrm{i}}+6.00 \hat{\mathrm{j}}[/tex]

In science, anything that has both a direction and a magnitude is referred to as a vector. They are typically represented by pointing arrows, the length of which denotes the size of the vector.

The component description of  A is just restated to constitute the answer to part (a):

A[tex]_x[/tex] = -3.00 , A[tex]_y[/tex] = 2.00

(a) [tex]\overrightarrow{\mathrm{A}}=\mathrm{A}_{\mathrm{x}} \hat{\mathrm{i}}+\mathrm{A}_{\mathrm{y}} \hat{\mathrm{j}}=-3.00 \hat{\mathrm{i}}+2.00 \hat{\mathrm{j}}[/tex]

(b) [tex]|\overrightarrow{\mathrm{A}}|[/tex] =  √(A[tex]_z[/tex]² + A[tex]_y[/tex]²) = √( (-3.00)² + (2.00)²) = 3.61

θ = tan -1 [tex]\left(\frac{\mathrm{A}_{\mathrm{y}}}{\mathrm{A}_{\mathrm{x}}}\right)[/tex] = tan-1 [tex]\left(\frac{2.00}{-3.00}\right)[/tex] = -33.7⁰

θ is in the second quadrant so θ = 180⁰ + (-33.7⁰) = 146⁰

(c) R[tex]_x[/tex] = 0, R[tex]_y[/tex] = -4.00 and [tex]\overrightarrow{\mathrm{R}}=\overrightarrow{\mathrm{A}}+\overrightarrow{\mathrm{B}}[/tex]   thus [tex]\overrightarrow{\mathrm{B}}=\overrightarrow{\mathrm{R}}-\overrightarrow{\mathrm{A}}[/tex]   and

B[tex]_x[/tex] = R[tex]_x[/tex] -A[tex]_x[/tex] = 0-(-3.00) = 3.00,

B[tex]_y[/tex] = R[tex]_y[/tex] - A[tex]_y[/tex] = -4.00-2.00= -6.00

therefore [tex]\overrightarrow{\mathrm{B}}=3.00 \hat{i}+6.00 \hat{j}[/tex].

To know more about Vector visit:

https://brainly.com/question/13322477

#SPJ9

The complete question is -

Vector  A  has a negative x component 3.00 units in length and a positive y component 2.00 units in length. (a) Determine an expression for  A in unit-vector notation. (b) Determine the magnitude and direction of  A. (c) What vector  B  when added to  A  gives a resultant vector with no x component and a negative y component 4.00 units in length.

Measuring human proportions on skeletal remains from ancient sites as well as among modern human populations is known as: anthropometry

The anthropometry is the part of science that studies the proportions of the human body, using non-invasive methods such as the measurement of body mass, height and width.

By using anthropometry it is possible to assess the size, proportions and composition of the human body which gives a measure that reflects the nutritional state of health and allows predicting the performance, health and survival of the individual under analysis.

It is the amount of mass associated with a person's body

Learn more about body mass at: brainly.com/question/10091149

#SPJ4

A football is thrown on a long pass. compared to the ball's initial vertical velocity, the vertical component of its velocity at the highest point is less

Velocity is defined as a vector measurement of the rate and the direction of motion, simply, velocity is the speed at which something moves in one direction. The speed of a car traveling north on a major freeway and the speed a rocket launching into the space can both be measured using velocity.

The SI units for the velocity are m/s (meters per second), but velocity may also be expressed in any units of distance per time, and the other units include miles per hour (mph), kilometers per hour (k/h), and kilometers per second (km/s).

At highest point the velocity of football is 0 as it is neither moving up or moving down for a moment so it is less than initial velocity. Magnitude of initial and final velocity is maximum in projectile motion.

To know more about speed visit: https://brainly.com/question/28224010

#SPJ4

When an object falls through the air, its velocity increases and its acceleration decreases.

A vector measurement of the rate and direction of motion is what is meant by the term "velocity." Simply said, velocity is the rate of movement in a single direction. Velocity may be used to gauge both the speed of a rocket launching into space and the speed of a car traveling north on a busy freeway.

As you might have anticipated, the velocity vector's scalar (absolute value) magnitude corresponds to the motion's speed. The first derivative of position with respect to time is known as velocity in calculus. There is a straightforward formula that combines rate, distance, and time to calculate velocity.

The following method is the most typical approach to get the constant velocity of an item traveling straight ahead:

r = d / t

The rate or speed is r. (sometimes denoted as v for velocity)

d is the traveled distance.

t is the amount of time needed to finish the movement

To learn more about the,  velocity  visit:

https://brainly.com/question/18545524

#SPJ4

The Industrial Revolution led to the creation of jobs in human resources because more people were going to work on farms and in small shops and is therefore denoted as option A.

This is referred to a period which experienced a change from a handicraft economy to one which was dominated by a lot of technological innovations and productions.

This period led to the production of a lot of machines which helped to make jobs easier for the workers. It led to the increase in the way different goods and products were processed which led to the need to employ more people to run the operations.

Working on farms with equipment such s tractors, plough etc and the creation of shops to sell more processed goods is what led to the creation of jobs in human resources.

Read more about Industrial Revolution here https://brainly.com/question/546336

#SPJ1

Answer: applied

Explanation:

Each capacitor carries a charge of 1/3q as they are identical.

#SPJ4

The density of a fish is controlled by the expansion and contraction of its air sacs while the density of a submarine is controlled by ballast tanks. It was emphasized earlier that buoyant forces does not equal an objects weight but does equal the weight of displaced water.

The three most fundamental characteristics of an object are mass, volume, and density. Volume indicates something's size, mass indicates how heavy it is, and density is calculated as mass divided by volume. Although you deal with mass and volume on a daily basis, the concept of density is less clear-cut and requires careful consideration.

Mass divided by density equals volume; and. Volume times density equals mass. A liquid's density is a gauge of how heavy it is relative to the amount being measured. The liquid that weighs heavier is more dense if you weigh two liquids with similar volumes or amounts.

The relationship between a substance's mass and the amount of space it occupies is known as its density (volume). The density of a substance is determined by the mass, size, and arrangement of its atoms.

To learn more about density , visit

brainly.com/question/14686323

#SPJ4

Answer:

27 m/s

Explanation:

Vf = Vo + a t

0  = vo + (-3.7)t

vo = 3.7t   use this value in the next equation

Displacement = vo t +   1/2 a t^2

100 = 3.7t^2 + 1/2 (-3.7)(t^2 )

100 = 1.85 t^2            t = 7.352 s

vo= 3.7 t = 3.7 * 7.352 = 27. m/s

The ways of transferring thermal energy are Conduction, Convection and Radiation.

Heat transfer is the movement of molecules from a region of higher temperature to a lower temperature. It can be done in three ways:

Conduction is the heat transfer done through direct contact between two bodies. Convection is the heat transfer done by movement of fluids such as water or air. Radiation is the heat transfer done by electromagnetic waves.

Therefore, the ways of transferring thermal energy are Conduction, Convection and Radiation.

To know more about Heat transfer

https://brainly.com/question/13433948

#SPJ4

Work done is 158 joule

Given that, the force of a moving object is,

F = (8i - 6j + 9k) N

The object is moving from point (0,10,8) to the point (6,12,20)

Now we can calculate the displacement by the formula,

dr = (x2-x2)i + (y2 - Y2)j + (z2 - z2)k

Put all the values from the given values.

dr = (6 - 0)x + (12 - 10)j + (20 - 8)k

dr = (6i-2j+12k) meters

Now, the work done can be calculated as,

W = F.dr

W = (8i - 6j + 9k).(6i-2j+12k)

W = 158 J

Hence, work done is 158 joule

Learn more about Work here:

https://brainly.com/question/25573309

#SPJ4

At speeds over 30 mph, you should maintain a following distance of at least three full seconds behind the vehicle ahead of you.

As a general rule and common sense at a speed of 30 mph you can leave three full seconds so that you can achieve a prudent distance between the car you are driving and the car in front in order to be able to perform some kind of maneuver if an accident or unforeseen event occurs.

To count the full three seconds you can use the technique of counting the Mississippis as follows: Mississippi one, Mississippi two, Mississippi three.

An accident is an unexpected event that generally causes damage, injury or negative consequences.

Learn more about accident at: brainly.com/question/28070413

#SPJ4

Cells can be observed under a brightfield microscope as translucent objects against a vivid background.

Objects that are translucent allow some light to pass through them. Translucent materials include certain polymers and frosted glass. Only a portion of the light that strikes transparent materials goes through. It takes the materials some time for the light to flow through them. Waxed paper, thin plastic sheets, butter paper, and vegetable oil are a few examples of translucent materials. This mnemonic should help you remember when to use transparent because transparent objects are clear and light may readily pass through them. The thing would be translucent if light still enters it, but it is less noticeable. An opaque object is one through which no light can flow.

To know more about translucent object, click here:

https://brainly.com/question/24662037

#SPJ4

Most active galactic nuclei are powered by: a. supermassive black holes.

A supermassive black hole is a type of huge black hole with a mass that can be millions to billions of times the mass of the Sun.

It is also known as SMBH or SBH. And inside of the back hole is a place where the material is compressed down to an enormously tiny point, and all the ideas of time and space completely break down.

A black hole is a very dense space in which gravity becomes so strong that not even light is able to get out, this is because matter is compressed into a very small space. A black hole is usually formed from the remains of a star that dies in a supernova.

Learn more about a black hole at: brainly.com/question/26587269

#SPJ4

The functions such as non-vertical, continuously differentiable, non-vertical tangent satisfy the conditions.

In mathematics, a differentiable function of one real variable is a function that has a derivative at each point in its domain. In other words, the graph of a differentiable function has a non-vertical tangent line at each interior point in its domain.

A smooth, differentiable function lacks any breaks, angles, or cusps (it is locally well approximated as a linear function at each interior point).

If the derivative f'(x 0) exists, a function f is said to be differentiable at x0 if x0 is an inner point in the domain of the function.

In other words, the point (x0, f(x0)) on the graph of f has a non-vertical tangent line. If f is differentiable at every point along U, then U is said to be differentiable.

If the derivative off is also a continuous function over the domain of the function ff, then f is said to be continuously differentiable.

In general, if f’s initial k derivatives are f prime (x), f prime (x), and lots, f(k)(x), then f is said to be of class Ck. f prime (x), f prime (x), lots, and f (k) prime (x) exist and are continuous across the function’s domain.

To know more about such differential function question, visit:

https://brainly.com/question/14290915

#SPJ4

The Patagonia region of Chile and Argentina features a large, elongated glacier approximately 90 km (56 mi) wide and 360 km (224 mi) long. this is an example of a(n): Ice field

The Patagonia region of Chile and Argentina is characterized by the largest ice fields in South America.

An ice field is a large mass of ice that covers part of the land.

The Patagonia is an area located in South America which is shared by Chile and Argentina.

Learn more about the Patagonia at: brainly.com/question/4206237

#SPJ4

On mars the rock that fall from rest in 6.5 s with an acceleration due to gravity of 3.77 m/s² would far a distance of: 79.64125 m

The free fall formula and the procedure we will use is:

h = (g * t²)/2

Where:

Information of the problem:

Applying final height formula we get:

h = (g * t²)/2

h = (3.77 m/s² * (6.5 s)²)/2

h = (3.77 m/s² * 42.25 s²)/2

h = 159.2525 m/2

h = 79.64125 m

It is when the object or mobile falls from a height (h) with a positive acceleration equal to the gravity, describing a vertical rectilinear travel.

Learn more about free fall at brainly.com/question/11257529

#SPJ4

C. When describing motion, a frame of reference is a system of reference points used to determine position and velocities of objects.

A frame of reference is an arbitrary set of axes with reference to which the position or motion of something is described or physical laws are formulated.

Frame of reference serves a valuable purpose, because it enables us to make more accurate measurement of our position, displacement, velocity and the total distance traveled.

Also, a frame of reference consists of an abstract coordinate system and the set of physical reference points that uniquely fix the coordinate system and take measurements within that frame.

In other words, it is a system or base, on which motion of an object is determined.

Thus, when describing motion, a frame of reference is a system of reference points used to determine position and velocities of objects.

Learn more about frame of reference here: https://brainly.com/question/1707361

#SPJ1

The following kinematic equation will be most useful for finding the ball’s initial velocity:

v = u + at

There are three kinematic equations, out of which any one equation can be used according to the given situation. These are:

In the above situation, a ball is rolled from the top of a table and the ball lands on the ground after 3 seconds with a final velocity of 3.5 m/s.

We have been provided by the final velocity, acceleration, and time taken by the ball, so the equation that would be most useful for finding the initial velocity will be, v =u +at.

Thus, the following kinematic equation will be most useful for finding the ball’s initial velocity:

v = u + at

Read more about kinematics equations:

brainly.com/question/12351668

#SPJ1