HELP ILL MARK BRIANLIEST

identify the independent variable
identify the dependent variable
Which statement best describes the relationship between the data (IV & DV)
Which statement best describes the relationship between the change in temperature data and the kinetic energy ?

a) The time after the release of the first stone that the second stone hits the water is 2.0 s.

b) 15.7 m/s is the initial speed of the second stone.

c)  The speed of the first stone as it hits the water is 15.7 m/s.

d) The speed of the second stone as it hits the water is 28.2 m/s.

Velocity is a vector quantity that measures both the speed and direction of an object's motion. It is equal to the rate of change of an object's position with respect to time. Velocity is usually represented by the symbol v and is measured in meters per second (m/s).

a) The time between first and second stone's release is 1.0 s. Since the time of release of first stone and the time of splash of both stones are same, the time between the release of second stone and the splash of both stones is 1.0 s.

Thus, the time after the release of the first stone that the second stone hits the water is 2.0 s.

b) The initial speed of the second stone can be calculated using the equation of motion,

v² = u² + 2as

where v is the final velocity, u is the initial velocity, a is the acceleration due to gravity (9.8 m/s²), and s is the displacement.

Substituting the values,

v² = (1.7)² + 2(9.8) * 59

v = 15.7 m/s

c) The speed of the first stone as it hits the water can be calculated using the equation of motion,

v² = u² + 2as

where v is the final velocity, u is the initial velocity, a is the acceleration due to gravity (9.8 m/s²), and s is the displacement.

Substituting the values,

v² = (1.7)² + 2(9.8) * 59

v = 15.7 m/s

d) The speed of the second stone as it hits the water can be calculated using the equation of motion,

v² = u² + 2as

where v is the final velocity, u is the initial velocity, a is the acceleration due to gravity (9.8 m/s²), and s is the displacement.

Substituting the values,

v² = (15.7)² + 2(9.8) * 59

v = 28.2 m/s

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Answer:

Explanation: Mass of an object

Distance traveled

Temperature in Celsius or Fahrenheit

Time elapsed

Area of a square or rectangle

Volume of a container

Energy consumed

Speed of a moving object

Amount of money

Density of a substance

Electric charge

Length of a rod or wire

Amount of substance (moles)

Angle of rotation

Electric potential (voltage)

Pressure of a gas or fluid

Frequency of a wave

Conductivity of a material

Viscosity of a fluid

Radioactivity

Magnetic field strength

Refractive index of a medium

Gravitational force

Work done

Power of an electrical device

Resistivity of a material

Specific heat capacity of a substance

Modulus of elasticity

Torque or moment of force

pH of a solution

Electrostatic charge

Atomic or molecular weight

Charge of an electron or proton

Electrical resistance

Illuminance or brightness

Concentration of a solute in a solution

Efficiency of a machine

Absorbance or transmittance of light

Electrochemical potential

Activity of a radioactive sample

Ratio of two lengths

Ratio of two areas

Ratio of two volumes

Ratio of two speeds

Ratio of two masses

Ratio of two times

Ratio of two temperatures

Ratio of two pressures

Ratio of two concentrations

Ratio of two densities

A cesium-133 atom's radiation goes through 1.5 million cycles in around 0.1633 microseconds (or 163.3 nanoseconds).

9,192,631,770 hertz (cycles per second) is the frequency of the microwave spectral line that the isotope cesium-133 emits. The basic unit of time is provided by this. Cesium clocks have an accuracy and stability of 1 second in 1.4 million years.

The radiation emitted by cesium-133 has a frequency of 9,192,631,770 cycles per second, or 9.192631770 109 Hz.

The following formula may be used to determine how long 1.5 million radiation cycles take to complete:

Time is equal to the frequency of cycles.

Plugging in the numbers, we get:

time = 1.5 million / 9.192631770 × 10^9 Hz

time = 1.632995101 × 10^-7 seconds

So it takes approximately 0.1633 microseconds (or 163.3 nanoseconds) for radiation from a cesium-133 atom to complete 1.5 million cycles.

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To resolve the star-planet system at a distance of 4 light-years, a telescope on Earth would need an aperture with a minimum diameter of 55.88 mm.

In optical microscopy, the Rayleigh criterion is frequently used to estimate the resolution of the microscope. The resolution limit imposed by this criterion has long been regarded as a roadblock to using an optical microscope to study biological phenomena at the nanoscale.

We can use the Rayleigh criterion,

θ = 1.22 λ / D

θ = angular resolution

λ = wavelength of light

D = diameter of the telescope's aperture

θ = arctan (r / d)

r = radius of the planet's orbit

d = distance to the star

Now, we use the given values,

r = 149.6×106 km = 149.6×109 m

d = 4 × 9.461×1015 m = 3.7844×1016 m

λ = 550 nm = 550×10-9 m

θ = arctan (r / d)

   =arctan (149.6×109 / 3.7844×1016) = 0.000012 radians

we can use the Rayleigh criterion,

θ = 1.22 λ / D

D = 1.22 λ / θ

D = 1.22 × 550×10-9 / 0.000012

D = 55.88 mm

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The correct equivalent equation from the options provided is:

w = (24.67 - h) / (h + 6)

What is Equivalent Equation?

An equivalent equation is an equation that has the same solution or solutions as the original equation. In other words, if two equations produce the same values for the variables, they are considered equivalent equations.

The equivalent equation for w, based on the given equation and solving for w, is:

w = (148 - 6h) / (h + 6)

To simplify this equation, we can factor out 6 from the numerator:

w = 6(24.67 - h) / (h + 6)

Now we can further simplify by dividing both numerator and denominator by 6:

w = (24.67 - h) / (h + 6)

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The speed of the waves can be expressed to two significant figures as 0.2 m/s. The unit for this expression is meters per second (m/s).

A wave crest is the highest point of a wave. It is the top of the wave, where the wave is moving most up and away from the equilibrium position. It is the point of highest amplitude (height) of the wave and is followed by a wave trough, which is the lowest point of the wave.

The speed of the waves can be calculated using the formula speed = distance over time.

We know the distance between wave crests is 9.0 m and the time it takes for 12 waves to pass the boat is 45 s. Therefore, the speed of the waves can be calculated as:

Speed = 9.0 m / 45 s

Speed = 0.2 m/s

The speed of the waves can be expressed to two significant figures as 0.2 m/s. The unit for this expression is meters per second (m/s).

This calculation shows that the speed of the waves passing the boat is 0.2 m/s. This speed can be further broken down into how many meters the waves travel in one second if necessary.

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To solve this problem, we can use Coulomb's law, which states that the electric force between two point charges is proportional to the product of their charges and inversely proportional to the square of the distance between them.

We can then use the electric force to find the electric field at the location of q3 and the initial acceleration of q3.

a) To find the electric field at the location of q3, we can first find the electric force on q3 due to q1 and q2 and then use the definition of the electric field, which is the electric force per unit charge. The electric force on q³ due to q¹ and q² is:

F1 = k x q¹ x q³/ r1²

F2 = k x q² x q³ / r2²

where r¹ and r² are the distances from q¹ and q² to q³, respectively, and k is Coulomb's constant.

Since q³ is equidistant from q¹ and q², we have r¹ = r² = 0.20 m. Substituting the given values, we get:

F1 = (9.0 x 10⁹ N-m²/C²) x (4.0 x 10⁻⁶ C) x (2.0 x 10⁻⁶C) / (0.20 m)² = 1.8 N

F2 = (9.0 x 10⁹ N-m⁻²/C²) x (-6.0 x 10⁻⁶ C) x (2.0 x 10⁻⁶C) / (0.20 m)² = -5.4 N

The negative sign of F2 indicates that the force on q³ due to q² is in the opposite direction to the force due to q¹.

The net electric force on q3 is the vector sum of the forces due to q1 and q2:

Fnet = F1 + F2 = 1.8 N - 5.4 N = -3.6 N

The electric field at the location of q³ is then:

E = Fnet / q³ = (-3.6 N) / (2.0 x 10⁻⁶ C) = -1.8 x 10⁻⁶N/C

The negative sign of the electric field indicates that the field is directed towards q².

b) To find the initial acceleration of q³, we can use Newton's second law, which states that the net force on an object is equal to its mass times its acceleration:

Fnet = ma

where m is the mass of q³ and a is its initial acceleration.

Substituting the given values, we get:

-3.6 N = (2.0 x 10⁻⁶ kg) x a

Solving for a, we get:

a = -1.8 x 10³ m/s²

The negative sign of the acceleration indicates that it is directed towards q².

c) The direction of the initial acceleration of q³ is towards q².

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A heat engine with a 65.0% Carnot efficiency is currently being developed. Between a reservoir that is 25.00C and one that is 3750C, a heat engine is operational.

The equation is: Carnot efficiency is equal to 1 - Tc/Th, wherein Tc is the cycle's cold end temperature and Th is its hot end temperature. In other words, efficiency is equal to one minus the difference between the hot and cold temperatures.

Explanation: The cold reservoir's temperature is TL=20C=20+273=293K. T L = 20 ∘ C = 20 + 273 = 293 K .

A Carnot cycle running between both of these two reservoirs has a thermal efficiency of = 1 TC/TH. This value exceeds the value of the Otto cycle, which is operating between similar reservoirs by a large margin.

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Answer:

Part A: [tex]1.97ms^{-1}[/tex] (2 s.f.)
Part B: 0.33m (2 s.f.)

Explanation:

Part A:

Frequency = [tex]\frac{1}{period} = \frac{1}{3}[/tex] Hz

Wavespeed = frequency x wavelength
Wavelength = distance between two crests = 5.90

Freq = 1/3 Hz

Therefore: Wavespeed = 1/3 x 5.90

                  Wavespeed = 1.967 ms^-1

Part B:
Amplitude = [tex]\frac{peak-to-peak- amplitude }{2}[/tex]

Peak to peak amplitude = 0.65m

Amplitude = 0.65/2 = 0.325m = 0.33m 2sf

The value of the charge on each particle is [tex]1.05 x 10^-8 C[/tex].

Coulomb's law is a fundamental principle of electrostatics that describes the interaction between electric charges. It states that the force between two point charges is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. We can use Coulomb's law to solve this problem. Mathematically,

[tex]F = k(q1q2)/r^2[/tex]

where F is the force of attraction or repulsion between the two charged particles,[tex]q1[/tex] and [tex]q2[/tex] are the magnitudes of the charges on the two particles, r is the distance between them, and k is Coulomb's constant, which has a value of [tex]9.0 x 10^9 Nm^2/C^2.[/tex]

In this problem, we know that the charges are equal and the distance between them is 10.0 cm. We also know that the force between them is 0.5 N. Therefore,

[tex]0.5 N = k(q^2)/(0.1 m)^2[/tex]

Solving for q, we get:

[tex]q = \sqrt{[(0.5 N)(0.1 m)^2/k]}[/tex]

[tex]q = \sqrt{(0.5 N)(0.01 m)/(9.0 x 10^9 Nm^2/C^2)}[/tex]

[tex]q = 1.05 x 10^-8 C[/tex]

Therefore, the value of the charge on each particle is [tex]1.05 x 10^-8 C.[/tex]

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Answer:A

Explanation:

Isotopes are members of a family of an element that all have the same number of protons but different numbers of neutrons. The number of protons in a nucleus determines the element's atomic number on the Periodic Table.

Humans would need a breathable environment like that on Earth in the living section of a colony on Venus in order to survive. Nitrogen, oxygen, and trace amounts of other gases, such as carbon dioxide, make up the majority of the atmosphere on Earth.

The clouds are made of sulfuric acid, and the atmosphere is primarily carbon dioxide, the same gas that causes the greenhouse effect on Venus and Earth. And the heated, high-pressure carbon dioxide acts corrosively at the surface.

For instance, compared to Earth, which has 99% nitrogen and oxygen in its atmosphere, Venus and Mars both contain more than 98% carbon dioxide and nitrogen.

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The frequency of the tsunami wave is estimated at  0.001 Hz

Frequency is described as the number of occurrences of a repeating event per unit of time

Using  the formula for the speed of a wave:

v = λ  x frequency

where v is the wave speed, λ is the wavelength, and f_ is the frequency.

frequency = v / λ

Substituting  the values given in the problem, we have

frequency  = 750 km/h / 270 km = 2.78 h^(-1)

f_ = 2.78 h^(-1) * (3600 s/h) = 1.00 x 10^(-3) s^(-1) or   0.001 Hz

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Answer:

A) P.E = 138.44 J

B) The velocity of swing at bottom, v = 3.33 m/s

C) The work done, W = -138.44 J

Explanation:

Given,

The mass of the child, m = 25 Kg

The length of the swing rope, L = 2.2 m

The angle of the swing to the vertical position, ∅ = 42°

A) The potential energy at the initial position ∅ = 42° is given by the relation

                               P.E = mgh joule

Considering h  = 0 for the vertical position

The h at ∅ = 42° is  h = L (1 - cos∅)

                              P.E = mgL (1 - cos∅)

Substituting the given values in the above equation

                              P.E = 25 x 9.8 x 2.2 (1 - cos42°)

                                     = 138.44 J

The potential energy for the child just as she is released, compared to the potential energy at the bottom of the swing is, P.E = 138.44 J

B) The velocity of the swing at the bottom.

At bottom of the swing the P.E is completely transformed into the K.E

                 ∴                 K.E = P.E

                                    1/2 mv² = 138.44

                                    1/2 x 25 x v² 138.44

                                           v² = 11.0752

                                            v = 3.33 m/s

The velocity of the swing at the bottom is, v = 3.33 m/s

C) The work done by the tension in the rope from initial position to the bottom

            Tension on string, T = Force acting on the swing, F

                           =

                           = - 2.2 x 25 x 9.8 [cos0 - cos 42°]

                           = - 138.44 J

The negative sign in the in energy is that the work done is towards the gravitational force of attraction.

The work done by the tension in the ropes as the child swings from the initial position to the bottom of the swing, W = - 138.44 J

The initial speed (magnitude of velocity) of the second ball thrown at an angle of 40 degrees above the horizontal is approximately 12.93 m/s.

Let's consider the motion of the second ball thrown at an angle of 40 degrees above the horizontal. We can break down its motion into horizontal and vertical components.

Given:

Time taken for the ball to return to its original level (time of flight): t = 2.75 seconds

Angle of projection (above the horizontal): θ = 40 degrees

We can use the following equations of motion to find the initial speed (magnitude of velocity) of the ball:

Horizontal motion:

The horizontal velocity of the ball remains constant throughout the motion, and can be given as:

vx = v0 * cos(θ), where v0 is the initial speed.

Vertical motion:

The vertical velocity of the ball changes due to the force of gravity. We can use the following equation:

vy = v0 * sin(θ) - g * t,

where;

Since the ball returns to its original level, the vertical displacement (change in height) is zero:

Δy = 0

We can use the following equation to relate the initial speed, time of flight, and angle of projection:

Δy = v0 * sin(θ) * t - (1/2) * g * t^2 = 0

Plugging in the values and solving for v0:

0 = v0 * sin(40) * 2.75 - (1/2) * 9.8 * (2.75)^2

v0 * sin(40) * 2.75 = (1/2) * 9.8 * (2.75)^2

v0 = (1/2) * 9.8 * (2.75)^2 / (sin(40) * 2.75)

v0 = 12.93 m/s (rounded to two decimal places)

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The mass of the remaining ice in the jar is 188 g.

What is Equilibrium?

Equilibrium refers to a state of balance or stability where opposing forces or factors are balanced, resulting in a state of overall stability and no net change. In various contexts, equilibrium can have different meanings and applications.

We can rearrange the equations to solve for the mass of ice remaining (mice):

Qtea = Qice

mtea * ctea * ΔT = mice * cice * ΔT

mice = (mtea * ctea * ΔT) / (cice * ΔT)

Plugging in the given values:

mtea = 188 g

ctea = 4186 J/kg◦ C (specific heat capacity of water)

ΔT = 30.7 - 26.6 = 4.1 ◦C (change in temperature of the tea)

cice = 4186 J/kg◦ C (specific heat capacity of ice)

mice = (188 * 4186 * 4.1) / (4186 * 4.1)

mice = 188 g

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The system's final temperature is roughly 16.7°C.

You may determine your substance's final heat by multiplying the temperature change by the initial temperature. Your water's final temperature would be 24 + 6, or 30 degrees Celsius, for instance, if it started off at 24 degrees Celsius.

The following is the formula for energy conservation:

Q1 + Q2 = 0

Q = mcΔT

Q1 + Q2 = 0

568.8

Simplifying and solving for

6394.4 - 106768 = 0

= 16.7°C

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The period of the pendulum with a length of 68 cm is 1.65 seconds.

What is period of the pendulum?

The period of a pendulum is the time taken for one complete back-and-forth swing or oscillation. It is the time taken for the pendulum to move from its highest point (the point of maximum displacement) to its lowest point and back again to the highest point. The period of a pendulum depends on its length and the acceleration due to gravity.

The period of a pendulum can be calculated using the formula:

T = 2π√(L/g)

where T is the period, L is the length of the pendulum, and g is the acceleration due to gravity (approximately 9.81 m/s²).

Converting the length of the pendulum to meters:

L = 68 cm = 0.68 m

Substituting the values into the formula:

T = 2π√(0.68 m / 9.81 m/s²)

Simplifying:

T = 2π√(0.0694 s²)

Calculating the square root:

T = 2π x 0.263 s

Simplifying:

T = 1.65 s

Therefore, the period of the pendulum with a length of 68 cm is 1.65 seconds.

What is an acceleration of the pendulum?

An acceleration of a pendulum refers to the rate at which its velocity changes as it swings back and forth. The acceleration of a pendulum is not constant but rather varies as the pendulum swings, with the greatest acceleration occurring at the endpoints of its swing, where it changes direction.The acceleration of a pendulum is directly proportional to the displacement of the pendulum from its equilibrium position.

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Complete question is: The period of the pendulum with a length of 68 cm is 1.65 seconds.

Answer:

ttrockstars

Explanation:

it's math you to be an expert at math thank you

According to the question the centripetal acceleration of the ball is 20 m/s².

Centripetal acceleration is the acceleration that a body experiences when it is moving in a curved path. It is always directed towards the center of the curve, and its magnitude is equal to the square of the body's velocity divided by the radius of the curve. It is also known as the radial acceleration, since it is directed along the radius of the curve.

The centripetal acceleration of an object in a circular path is given by the equation:

[tex]a_c[/tex] = v²/r
where a_c is the centripetal acceleration, v is the speed of the object, and r is the radius of the circular path.
In this case, the speed of the ball is 4 m/s, and the radius of the circular path is 0.8 m. Plugging these values into the equation, we get:

[tex]a_c[/tex] = 4²/0.8 = 16/0.8 = 20 m/s²
Therefore, the centripetal acceleration of the ball is 20 m/s².

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The factor that leads to loess deposit is when the wind carries fine sediment. That is option C.

The loess deposits are those deposits that are usually found at the edge of deserts.

The major factor that causes the formation of loess is the wind because they are entrained, transported, and deposited by the wind.

The fine particles carried by wind contains find grained sediments, organic particles that are capable of forming loess.

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The difference in these numbers is likely due to the fact that there are a few very highly paid female tennis players who skew the average upwards.

Average is a term used to describe a value that is representative of a set of data. It is calculated by adding up all the values in a set and dividing by the number of values in the set. Average can be used to describe the mean, median, or mode of a set of data. It is often used to average out the highs and lows in a set of data, to give an overall picture of the data set. Average can also be used to compare different sets of data to each other.

The median, however, only takes into account the middle value of the data set, so it doesn't take into account outliers like the highly paid female tennis players. This is why the median is usually considered a better measure of central tendency than the average.

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Answer:

Rayleigh scattering

Explanation:

The blue color of the sky is due to a phenomenon called Rayleigh scattering. When sunlight enters the Earth's atmosphere, the shorter blue wavelengths of light are scattered more than the other colors by the tiny molecules of nitrogen and oxygen in the air. This causes the blue light to be redirected in many different directions, making the sky appear blue to our eyes. The other colors of light are scattered as well, but to a lesser extent, which is why the sky appears blue instead of a mixture of all colors. This effect is also the reason why the sun appears more yellow, orange or red during sunrise or sunset, when its light has to travel through more of the Earth's atmosphere before reaching our eyes, causing the shorter blue wavelengths to be scattered even more, leaving behind the longer wavelengths of light.

The final temperature after adding the ice to the water and calorimeter will be approximately 8.37 ◦C.

What is Temperature?

Temperature is a measure of the average kinetic energy of the particles in a substance or system. It is a scalar quantity that indicates how hot or cold an object or medium is. Temperature is commonly measured using various scales, such as Celsius (°C), Fahrenheit (°F), and Kelvin (K), which represent different reference points and units of measurement.

Since energy is conserved, we can set Q_ice equal to Q_water+calorimeter:

m_ice * c_ice * ΔT_ice = (m_water + m_calorimeter) * c_water+calorimeter * ΔT_water+calorimeter

27 g * 2090 J/kg ◦C * (T_f + 65) = (525 g + 80 g) * (4186 J/kg ◦C + 387 J/kg ◦C) * (T_f - 25)

Simplifying and solving for T_f:

27 * 2090 * (T_f + 65) = 605 * (T_f - 25)

56130 T_f + 361350 = 605 T_f - 15125

56130 T_f - 605 T_f = -15125 - 361350

-44,970 T_f = -376475

T_f = (-376475) / (-44,970)

T_f ≈ 8.37 ◦C

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With time, the hot chocolate's thermal energy will permeate into the atmosphere, causing the cup to chill.

Conduction, which transfers heat through direct touch, transports heat from the hot chocolate to the mug. As the molecules of the hot chocolate clash with those of the mug, energy is transferred to both of them as well as to the surrounding air.

Conduction into the metal spoon will speed up the transfer of heat from the cocoa. The heat will be dispersed throughout the spoon's body because it is a thermal conductor.

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Two or greater sources are said to be coherent if they emit waves that have the identical wavelength (or frequency) and amplitude and which maintain a steady phase difference.

If two sources have the identical wavelength, frequency, and segment difference, they are said to be coherent. Therefore, we can conclude that coherent sources have the identical wavelength.

Two microwave coherent factor sources emitting waves of wavelenths λare positioned at 5λdistance apart. The interference is being observed on a flat non-reflecting surface alongside a line passing through on sources ,in a course perpendicular to the line joining the two sources

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The Universe became dominated by matter instead of radiation at a redshift of around 3300.

To determine at what redshift the Universe became dominated by matter, we need to find the redshift at which the energy density of matter becomes equal to the energy density of radiation.

Let's start with the energy density of radiation, which can be calculated using the Stefan-Boltzmann law:

$[tex]u_{rad} = \frac{4\sigma}{c}T^4$[/tex]

where $\sigma$ is the Stefan-Boltzmann constant, $c$ is the speed of light, and $T$ is the temperature of the radiation. Since we are assuming that the cosmic microwave radiation is a black-body radiation, we can use the temperature of 2.73 K, which corresponds to the peak of the radiation curve:

[tex]$u_{rad} = \frac{4\sigma}{c}(2.73K)^4 \approx 0.261 \text{ eV/cm}^3$[/tex]

Next, let's calculate the energy density of matter. We know that the number density of baryons is [tex]$n_b \approx \frac{1}{10^9}n_{\gamma}$, where $n_{\gamma}$[/tex] is the number density of photons. Since we are assuming that the photon-to-baryon ratio is constant, we can write:

[tex]$\frac{\rho_b}{\rho_{\gamma}} = \frac{m_b n_b}{\frac{4}{3}\sigma T^4} = \frac{3m_b}{4\sigma T^3 n_{\gamma}} \approx \frac{3m_b}{4\sigma T^3}\frac{1}{n_{\gamma}}$[/tex]

where $m_b$ is the mass of a baryon. Substituting the values, we get:

[tex]$\frac{\rho_b}{\rho_{\gamma}} \approx 4.15 \times 10^{-10}$[/tex]

Since the total energy density of the Universe is given by:

[tex]$\rho_{tot} = \rho_b + \rho_{\gamma}$[/tex]

we can write:

[tex]$\frac{\rho_b}{\rho_{tot}} = \frac{\rho_b}{\rho_b + \rho_{\gamma}} \approx \frac{\rho_b}{\rho_{\gamma}} = 4.15 \times 10^{-10}$[/tex]

At the redshift $z$, the energy density of radiation will be diluted by a factor of $[tex](1+z)^4[/tex]$, while the energy density of matter will be diluted by a factor of $[tex](1+z)^3[/tex]$. Thus, at some redshift $z$, we will have:

$  [tex]\frac{\rho_b}{\rho_{tot}} = \frac{\rho_b}{\rho_b + \rho_{\gamma}} = \frac{1}{1+z}\frac{3m_b}{4\sigma T^3 n_{\gamma}}[/tex]   $

Setting this equal to the value we calculated above, we can solve for $z$:

$   [tex]\frac{1}{1+z}\frac{3m_b}{4\sigma T^3 n_{\gamma}} \approx 4.15 \times 10^{-10}[/tex]  $

$  [tex]1+z \approx \frac{3m_b}{4\sigma T^3 n_{\gamma}}\frac{1}{4.15 \times 10^{-10}}[/tex]  $

$ [tex]z \approx 3300[/tex] $

Therefore, the Universe became dominated by matter instead of radiation at a redshift of around 3300.

To know more about density:

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Answer: d. increase

Explanation:

If the sun were more massive, the gravitational force between the sun and Earth would increase. This means that Earth's gravity with the sun would also increase. Therefore, the correct answer is (D) increase.

The gravitational force between two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. So, if the mass of one of the objects increases, the gravitational force between them will also increase. In this case, if the mass of the sun were to increase, the gravitational force between the sun and Earth would become stronger, and hence, Earth's gravity with the sun would also increase.