The temperature of the surface of the Sun is 5500°C.

a. What is the average kinetic energy, in joules, of hydrogen atoms on the surface of the Sun?
b. What is the average kinetic energy, in joules, of helium atoms in a region of the solar corona where the temperature is 6.00 times 10^5 K?

Answers

Answer 1

Answer:

a. the average kinetic energy of hydrogen atoms is  1.20 × 10^-19J

b. the average kinetic energy of helium atoms is 1.24 × 10^-17J

Explanation:

The computation is shown below;

As we know that

Kinetic energy = 3 ÷ 2 kT

where,

K = Boltzmann constant

And, T = Temperature

a. Now the temperature in kelvin is

T = (5,500 × (°C ÷ K) + 273.15 K)

= 5773.15 K

As

Kinetic energy = 3 ÷ 2 kT

So now 1.38 × 10^-23 J/K for K would be substituted and 5773.15 K for Temperature T

Now Kinetic energy is

= 3 ÷ 2 (1.38 × 10^-23 J/K) ( 5773.15 K)

= 1.20 × 10^-19J

hence, the average kinetic energy of hydrogen atoms is  1.20 × 10^-19J

b. As

Kinetic energy = 3 ÷ 2 kT

now 1.38 × 10^-23 J/K for K would be substituted and 6 × 10^5K for Temperature T

Now Kinetic energy is

= 3 ÷ 2 (1.38 × 10^-23 J/K) (6 × 10^5K )

= 1.24 × 10^-17J

hence, the average kinetic energy of helium atoms is 1.24 × 10^-17J


Related Questions

A 40-kg person is climbing 3 m up a flight of stairs in 6 seconds. How much work did they do climbing the stairs? (acceleration due to gravity = 10 m/sec2)

Answers

Answer:

1200J

Explanation:

W.D=mass×accelerarion due to gravity×distance

W.D=40kg×10m/s²×3m

W.D=1200kgm²/s²

W.D=1200J

A 40 kg person is climbing 3 m up a flight of stairs in 6 seconds, then the work done by the person to climb the stairs is 1200 J.

What is Work done?

When we apply a force called "F" to a block, the body moves with an acceleration or, additionally, its speed changes depending on the force's direction. The system's kinetic energy changes depending on whether the speed increases or decreases.

Energy must be transformed into another form because, as far as we are aware, it cannot be created or destroyed. In this view, it is referred to as work completed.

[tex]Work\ done = Force*Distance[/tex]

and Force = mg

Substitute all the values in the above formula,

W.D = 40 kg × 10 m/s² × 3 m

W.D = 1200 kg m²/s² or,

W.D = 1200 J

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What is albedo? What on Earth has high albedo?

Answers

Answer:

The fraction of incident light or radiation reflected by a surface or body, commonly expressed as a percentage.

2.

biology The whitish inner portion of the rind of citrus fruits that is a source of pectin, commonly referred to as the pith.

Explanation:

The sound level at a distance of 1.48 m from a source is 120 dB. At what distance will the sound level be 70.7 dB?

Answers

Answer:

The second distance of the sound from the source is 431.78 m..

Explanation:

Given;

first distance of the sound from the source, r₁ = 1.48 m

first sound intensity level, I₁ = 120 dB

second sound intensity level, I₂ = 70.7 dB

second distance of the sound from the source, r₂ = ?

The intensity of sound in W/m² is given as;

[tex]dB = 10 Log[\frac{I}{I_o} ]\\\\For \ 120 dB\\\\120 = 10Log[\frac{I}{1*10^{-12}}]\\\\12 = Log[\frac{I}{1*10^{-12}}]\\\\10^{12} = \frac{I}{1*10^{-12}}\\\\I = 10^{12} \ \times \ 10^{-12}\\\\I = 1 \ W/m^2[/tex]

[tex]For \ 70.7 dB\\\\70.7 = 10Log[\frac{I}{1*10^{-12}}]\\\\7.07 = Log[\frac{I}{1*10^{-12}}]\\\\10^{7.07} = \frac{I}{1*10^{-12}}\\\\I = 10^{7.07} \ \times \ 10^{-12}\\\\I = 1 \times \ 10^{-4.93} \ W/m^2[/tex]

The second distance, r₂, can be determined from sound intensity formula given as;

[tex]I = \frac{P}{A}\\\\I = \frac{P}{\pi r^2}\\\\Ir^2 = \frac{P}{\pi }\\\\I_1r_1^2 = I_2r_2^2\\\\r_2^2 = \frac{I_1r_1^2}{I_2} \\\\r_2 = \sqrt{\frac{I_1r_1^2}{I_2}} \\\\r_2 = \sqrt{\frac{(1)(1.48^2)}{(1 \times \ 10^{-4.93})}}\\\\r_2 = 431.78 \ m[/tex]

Therefore, the second distance of the sound from the source is 431.78 m.

A harmonic oscillator starts with an amplitude of 20.0 cm. After 10.0 s, the amplitude decreases to 15.0 cm. If the linear damping coefficient is 2.00 Ns/m, how much mass is oscillating

Answers

Answer: the amount of mass is oscillating is 34.8 kg

Explanation:

Given that;

amplitude A = 20.0 cm

time t = 10 s

amplitude decreases x = 15.0 cm

damping coefficient b = 2.00 N.s/m

amount of mass is oscillating = ?

we know that; amplitude can be expressed as;

x = Ae^-(∝t)

we substitute

15 = 20e^-∝(10)

∝ = 0.02877 s⁻¹

Hence mass m will be;

m = b/2∝

we substitute

m = (2 N.s/m) / ( 2 × 0.02877 s⁻¹)

m = 34.8 kg

Therefore the amount of mass is oscillating is 34.8 kg

why did the following change occur? the snow that covered the ground all winter began to melt, temperatures rose, and flowers started to bloom
A.) Days became shorter.
B.) The Earth tilted away from the sun
C.) The sun's rats became for concentrated.
D.) Earth completed one revolution

Answers

Answer:C

Explanation:

Answer:

B

Explanation:

Because the earth shifts axes points so it would make it cllser hotter etc

Which statement describes the factors that affect the force of friction? Question 2 options: Friction is always the same no matter what Friction increases as the normal force (weight) increases, and also depends on the surface Friction is greater when objects are barely touching Friction is greater on slippery surfaces

Answers

Answer:

  (b)  Friction increases as the normal force (weight) increases, and also depends on the surface

Explanation:

The coefficient of friction relates the normal force between surfaces to the friction force opposing motion. The coefficient depends on the surface.

The appropriate choice is ...

  Friction increases as the normal force (weight) increases, and also depends on the surface

1 What is the resistance of the inductive coil
takes 5A current across 240V, 50Hz supply
at 0.8 power factor?
A 48
B 4250
C 38.40
D 26.60​

Answers

Answer:

38.40

Explanation:

This is the answer for this question

PLEASE HELP!!! Which process in living things evolved as oxygen levels increased in Earth’s atmosphere?


glycolysis


photosynthesis


fermentation


aerobic respiration

Answers

Answer: Areobic Resporation

Explanation; -Aerobic respiration is the process in living things that evolved as oxygen levels increased in earth's atmosphere.

Answer; -Aerobic respiration; Explanation; -Aerobic respiration is the process in living things that evolved as oxygen levels increased in earth's atmosphere.

The Starship Enterprise is powered by combining matter with antimatter. Suppose 1 kg of each are combined and ejected backward at the speed of light, what is the final speed of the Enterprise starting from rest? Assume that the mass of the Enterprise is 10,000 kg and the spaceship does not reach relativistic speed.

Answers

Answer:

The Starship Enterprise is powered by combining matter with antimatter. Suppose 1 kg of each are combined and ejected backward at the speed of light, what is the final speed of the Enterprise starting from rest? Assume that the mass of the Enterprise is 10,000 kg and the spaceship does not reach relativistic speed.

5. 3 women push a stalled car. Each woman pushes with a 400N force. What is the mass of the car if the car accelerates at 0.85 m/s??

Answers

Answer:

470.59 kg

Explanation:

The the mass of the car can be found by using the formula

[tex]m = \frac{f}{a} \\ [/tex]

f is the force

a is the acceleration

From the question we have

[tex]m = \frac{400}{0.85} \\ = 470.58823...[/tex]

We have the final answer as

470.59 kg

Hope this helps you

using the forces applied to the system, determine the mechanical advantage of this pulley​
A) 0.5
B) 2.0
C) 50
D) 100

Answers

Answer: the answer is B. 2.0

Explanation:

g A proton and an alpha particle are released from rest at different locations from the negative plate of a charged parallel plate capacitor. The plates are 15 mm apart, and they are charged to a potential difference of 680 V. The alpha particle is placed at the point where the potential is 600 V. Where do you need to place the proton so that both particles reach the negative plate with the same speed

Answers

Answer:

d₂ = 6.18 mm

Explanation:

We can work on this interesting exercise using the concepts of energy conservation

alpha (1) particle, with have a charge q = 2e

Starting point

            Em₀ = U = q V₁

final point

            [tex]Em_{f}[/tex] = ½ m v²

             Em₀ = Em_{f}

            2eV₁ = ½ m₁ v²

           v² =[tex]\frac{4 \ e \ V_{1}}{m_{1} }[/tex]

proton (2) particle, with have a charge q = e

Starting point

          Em₀ = qV₂

Final point

          Em_{f} = ½ m₂ v²

          Em₀ = Em_{f}

          eV₂ = ½ m₂ v²

          v² = [tex]\frac{2 \ e \ V_{2} }{m_{2} }[/tex]

in the exercise, it should be noted that the two particles have the same velocity when reaching the plate, therefore let us solve the velocity in each equation and equal

        \frac{4 \ e \ V_{1}}{m_{1} }= \frac{2 \ e \ V_{2} }{m_{2} }

         [tex]V_{2} = \frac{2 m_{2} }{m_{1} } \ V_{1}[/tex]

the alpha particle is composed of two protons and two neutrons, therefore in first approximation

          m₁ = 4 m₂

subtitute

         V₂ =[tex]\frac{1}{2}[/tex] V₁

let's calculate

         V₂ = [tex]\frac{1}{2}[/tex] 600

         V₂ = 300 V

To find the distance we use the relationship between the electric field and the potential difference

         V = -d E

The electric field between the plates is constant, so

          E = - V / d = - V₂ / d₂

          d₂ = [tex]\frac{V_{2} }{V} \ d[/tex]

let's calculate

          d₂ = [tex]\frac{300}{680} \ 15[/tex]  

          d₂ = 6.18 mm

Draw the Free- Body diagram of the 37 kilogram glass falling to the floor in a vacuum.



Then, use Newton’s Second Law to calculate how much force the glass hits the floor with.

Answers

Answer:

362.6 N

Explanation:

[tex]F_{g}=mg[/tex]

[tex]F_{g}=37\cdot9.8[/tex]

[tex]F_{g}=362.6\ N[/tex]

Therefore, the force that the glass hits the floor with is 362.6 N

Which list ranks the three types of radiation from lowest penetrating power to
highest penetrating power?
A. Gamma < alpha < beta
B. Beta < alpha < gamma
C. Alpha < beta < gamma
D. Gamma < beta < alpha

Answers

Answer:gamma>beta>alpha

Explanation: Just took the test

A rod is made of three segments of equal length with different masses. The total mass of the rod is 6m. Will the moment of inertia of the rod be (i) greater about the left end, (ii) greater about the right end, or (iii) the same about both ends

Answers

Answer: (iii) the same about both ends

Explanation:

The moment of inertia is the sum of the square of the distance from the axis of massage and rotation of each length of the rod. The moment of inertia can be expressed as I = imiri2. The connection of the rod is the product of the moment length and distance (square), so it is the same at both ends.

The moment of inertia depends on the distribution of mass and the square of the distance from the axis.

The moment of inertia of the rod is the same about both ends. Hence, option (iii) is correct.

What is the moment of inertia?

The degree measure of the resistance of an object towards an angular acceleration about the given axis is known as the moment of inertia of an object.

Given data -

The total mass of rod is, M = 6m.

The moment of inertia is the sum of the square of the distance from the axis of massage and rotation of each length of the rod. The mathematical expression is given as,

[tex]I = M \times r^{2}[/tex]

Since the connection of the rod is the product of the moment length and distance (square), so it is the same at both ends.

Thus, we can conclude that the moment of inertia of the rod is the same about both the ends.

Learn more about the moment of inertia here:

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which law of thermodynamics would be violated if heat were to spontaneously flow between two abject which are in thermal equilibrium?

Answers

Answer:

The law zero of thermodynamics.

Explanation:

The law zero of thermodynamics, which tells us that heat flows from a body at a higher temperature to another body with lower temperature, when the heat transfer is zero, it is said that the two bodies are in thermal equilibrium, their temperatures are equal

A 7750 kg space probe, moving nose-first toward Jupiter at 179 m/s relative to the Sun, fires its rocket engine, ejecting 72.0 kg of exhaust at a speed of 230 m/s relative to the space probe. What is the final velocity of the probe?

Answers

Answer:

179.47m/s

Explanation:

Using the law of conservation of momentum

m1u1 + m2u2 = (m1+m2)v

m1 and m2 are the masses

u1 and u2 are the initial velocities

v is the final velocity

Substitute

7750(179)+72(230) = (7750+72)v

1,387,250+16560 = 7822v

1,403,810 = 7822v

v = 1,403,810/7822

v= 179.47m/s

Hence the final velocity of the probe is 179.47m/s

The distance between the object and its image formed by a plane mirror appears to be 24 cm. What is the distance between the mirror and the object?​

Answers

Answer:

in a plane mirror distance of object from mirror is equal to distance of image

so it will be 24 ÷ 2 = 12 cm

8
9
TIME REMAINING 10:34
Which statement describes an atomic nucleſus?
An atomic nucleus is negatively charged.
An atomic nucleus has no electrical charge.
An atomic nucleus consists of mostly empty space.
An atomic nucleus contains most of the atom's mass,

Answers

An atomic nucleus . . .

-- contains all of the atom's positive charge

-- contains almost all of the atom's mass

-- contains none of the atom's negative charge.

Answer:

An atomic nucleus . . .

-- contains all of the atom's positive charge

-- contains almost all of the atom's mass

-- contains none of the atom's negative charge.

Explanation:

yaaaaaa what the person on top said

The energy flow per unit time per unit area (S) of an electromagnetic wave has an average value of 310 mW/m2. The maximum value of the magnetic field in the wave is closest to:

Answers

Answer:

5.096*10^-8

Explanation:

Given that

The average value of the electromagnetic wave is 310 mW/m²

To find the maximum value of the magnetic field the wave is closest to, we say

Emax = √Erms

Emax = √[(2 * 0.310 * 3*10^8 * 4π*10^-7)]

Emax = √233.7648

Emax = 15.289

Now, with our value of maximum electromagnetic wave gotten, we divide it by speed of light to get our final answer

15.289 / (3*10^8) = 5.096*10^-8 T

Suffice to say, The maximum value of the magnetic field in the wave is closest to 5.096*10^-8

I AM 145 LBS. I FELL FROM A TABLE TOP THAT WAS 4.5 FEET HIGH AND LANDED ON MY HAND WHICH WAS TURNED BACKWORDS. I BROKE BOTH MAJOR BONES IN MY ARM DIRECTLY ABOVE MY WRIST. WHAT IS THE FORMULA OF THE FORCE AND WEIGHT HITTING THE FLOOR

Answers

Yes because 15.654367 divided by your mom = my 2nd dog

A jet pilot puts an aircraft with a constant speed into a vertical loop. (a) Which is greater, the normal force exerted on the seat by the pilot at the bottom of the loop or that at the top of the loop

Answers

Answer:

A jet pilot puts an aircraft with a constant speed into a vertical loop is explained below in complete details.

Explanation:

Well, the difficulty does not provide the pilot's mass (or weight in regular gravity), but the difficulty can be resolved and declared in courses of m (the pilot's mass).

When the jet is at the foundation of the circuit, a free-body chart displays the centripetal energy working upward approaching the middle of the loop, and the sound force of the chair and the pilot also upward. The pilot's weight (mg) is earthward. From Newton's second law:

?F(c) = ma(c) = n - mg

n = mg + ma(c)

= m[g + a(c)]

Since centripetal acceleration equals v² / r, the equalization enhances:

n = m[g + (v² / r)]

4. A box of old textbooks is on the middle shelf in the bookroom 1.3 m from the floor. If the janitor relocates the box to the shelf that is 2.6 m from the floor, how much work does he do on the box. The box has a mass of 10.0 kg.

Answers

Answer:

127.53 J

Explanation:

Given that

Height of the floor, h = 1.3 m

Acceleration due to gravity, g = 9.81 m/s²

Mass of the box, m = 10 kg

To find the work done on the box by the janitor, we use the formula for potential energy. Remember that potential energy is actually the energy stored in an object as a result of its position.

P.E = mgh, substituting each parameters for its value, we then have

P.E = 10 * 9.81 * 1.3

P.E = 127.53 J

Therefore, we can conclude that the amount of work done on the box by the janitor is 127.53 J

If vector A= aj^ and vector B = bj^, then vector A×B is equal to​

Answers

Answer:

0 because j×j =0

Explanation:

so a×b is 0

Electrical equipment in an office takes a current of 13 A from a 240 V supply.
Estimate the cost per week of electricity if the equipment is used for 30 hours each
week and 1 kWh of energy costs Rm0.50​

Answers

Answer:

The cost per week of electricity is Rm 46.8

Explanation:

Electrical Power and Energy

The electrical power consumed by an appliance connected to a voltage V and carrying a current I is given by:

P = V.I

The energy consumed by an electrical appliance of power P during a time t is:

E = P.t

The electrical equipment in an office takes I=13 A when connected to a V=240 V supply.

The power consumed is:

P = 240 V * 13 A

P = 3,120 Watt

Converting to Kilowatt:

P = 3,120/1,000 KW

P = 3,12 KW

If the equipment is used t=30 hours each week, the energy is:

E = 3.12 KW * 30 h

E = 93.6 KWh

Since the cost of each KWh is Rm 0.50, the weekly cost of electricity is:

C = 93.6 * 0.50 = 46.8

The cost per week of electricity is Rm 46.8

What type of simple machine is an electric fan?

Answers

Answer:

An electric fan is considered to be a mixture of several simple machines. It includes the Wheel and Axle type, wedges, and the Inclined plane types. The blades of an electric fan are the inclined planes and the wedges.

What are earth crossing asteroids and how do we monitor them

Answers

Answer:

Earth-crossing asteroid, asteroid whose path around the Sun crosses Earth's orbit. Two groups of such asteroids—Aten and Apollo asteroids—are distinguished by the size of their orbits and how closely they approach the Sun.

Explanation:

A solid sphere made of plastic density of 1350 kg/m3 has a radius of 35.0 cm. It is suspended by a massless cord. 75% of its volume is in water and 25% of it is in oil. The density of water is 1000 kg/m3 and the density of the oil is 850 kg/m3. What is the total buoyant foce on the sphere

Answers

Answer:

B_total = 1694 N ,  T = - 937.7 N

Explanation:

This is an exercise of the Archimedes principle that establishes that the thrust of a liquid is equal to the weight of the dislodged volume

          B = ρ g V_body

For this case we will assume that the weight of the body is in equilibrium with the thrust of the liquids and the tension of the rope

          B₁ + B₂ - W + T = 0

         

suppose liquid 1 is water and liquid 2 is oil

          ρ₁ g V₁ + ρ₂ g V₂ = W

for body weight let's use the definition of density

         ρ = m / V

         m = ρ V

         

we substitute

         T = ρ g V - (ρ₁ g V₁ + ρ₂ g V₂)

In the problem we are told that the volume in the water is 75% and the volume in the oil is 25% of the body's volume.

         T = ρ g V - g (ρ₁ 0.75 V + ρ₂ 0.25 V)

         

let's calculate the volumes

Body

         V = 4/3 π r³

liquid 1 (water)

         V₁ = 0.75 V = ¾ V

liquid 2 (oil)

         V₂ = 0.25 V = ¼ V

we substitute

        T = ρ g [tex]\frac{4}{3}[/tex] π r³ - g (ρ₁ [tex]\frac{3}{4}[/tex]  [tex]\frac{4}{3}[/tex] π r³ + ρ₂  [tex]\frac{1}{4}[/tex] [tex]\frac{4}{3}[/tex] π r³)

        T = [tex]\frac{4}{3}[/tex] ρ g r³ - g π r³ (ρ₁ + [tex]\frac{1}{3}[/tex] ρ₂)

The term of the floating force is

        B_total = g π r³ (ρ₁ + [tex]\frac{1}{3}[/tex] ρ₂)

let's calculate its value

        B_total = 9.8 π 0.35³ (1000 + ⅓ 850)

        B_total = 1694 N

therefore the tension in the string is

         T = [tex]\frac{4}{3}[/tex] 1350 9.8 0.35³ - 1694

         T = 756.3 - 1694

         T = - 937.7 N

The negative sign indicates that the system tends to come out of the liquid, for which a downward force must be applied to keep it in position.

what is the shallowest part of the ocean ecosystem is called

Answers

Answer:

intertidal zone.

the shallowest part of the ocean ecosystem, where the ocean floor os covered and uncovered as the tide goes in and out. Plankton. the organisms that float on the water in aquatic ecosystems and are unable to swim.

On a part-time job, you are asked to bring a cylindrical iron rod of density 7800 kg/m^3 , length 92.4 cm and diameter 2.15 cm from a storage room to a machinist. Calculate the weight of the rod, w. Assume the free-fall acceleration is g =9.81m/s^2

Answers

Answer:

25.68 N

Explanation:

From the question given above, the following data were obtained:

Density of cylindrical rod = 7800 kg/m³

Length = 92.4 cm

Diameter = 2.15 cm

Acceleration due to gravity (g) = 9.8 m/s²

Weight of rod =?

Next, we shall determine the volume of the rod. This can be obtained as follow:

Height (h) = 92.4 cm

Diameter (d) = 2.15 cm

Pi (π) = 3.14

Volume (V) =?

V = π(d/2)²h

V = 3.14 × (2.15/2)² × 92.4

V = 335.29 cm³

Next, we shall convert 335.29 cm³ to m³. This can be obtained as follow:

1 cm³ = 1×10¯⁶ m³

Therefore,

335.29 cm³ = 335.29 cm³ × 1×10¯⁶ m³ / 1 cm³

335.29 cm³ = 0.00033529 m³

Thus, 335.29 cm³ is equivalent to 0.00033529 m³.

Next, we shall determine the mass of the rod. This can be obtained as follow:

Density of rod = 7800 kg/m³

Volume of rod = 0.00033529 m³.

Mass of rod =?

Density = mass /volume

7800 = mass / 0.00033529

Cross multiply

Mass of rod = 7800 × 0.00033529

Mass of rod = 2.62 Kg

Finally, we shall determine the weight of the rod. This can be obtained as follow:

Mass (m) of rod = 2.62 Kg

Acceleration due to gravity (g) = 9.8 m/s²

Weight (W) of rod =?

W = m × g

W = 2.62 × 9.8

W = 25.68 N

Therefore, the weight of the rod is 25.68 N

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