A moving walkway has a speed of 0.5 m/s to the east. A stationary observer
sees a man walking on the walkway with a velocity of 0.8 m/s to the east.
What is the man's velocity relative to the moving walkway?

Answer:

A) 1236 N

B) Nw = µ_s•N

C) d_max = 1.525 m

Explanation:

From the question, "smooth vertical wall" means that there is no friction there and thus the only vertical forces are the weights of the ladder and painter and the normal force at the floor.

a) Mass of ladder = 14 kg

Mass of painter = 8M = 8 * 14 = 112 kg

Thus, magnitude of normal force is;

N = total mass x acceleration due to gravity = (14 + 112)9.8

N = 1236 N

(b) Sum of the moments about the base of the ladder:

ΣH = 0

Nw - µ_s•N = 0

Nw = µ_s•N

c) Since they are the only two horizontal forces in play, we know that

Nw = Ff where Ff is the friction force at the floor.

Ff = µ_s*N = 0.39 × 1236

Ff = 482.04 N

So, to find maximum distance painter can stand without slipping, we'll use the formula ;

Nw(Lsinθ) = (Mgcosθ)(L/2) + (8Mgcosθ * d_max)

Plugging in the relevant values, we have;

482.04(2.7*sin55) = ((14 × 9.8cos55)*(2.7/2)) + (8*14*9.8cos55 * d_max)

1066.133 = 106.238 + 629.5575*d_max

629.5575*d_max = 1066.133 - 106.238

629.5575*d_max = 959.895

d_max = 959.895/629.5575

d_max = 1.525 m

A) The magnitude of the normal force is  1236 N

B) expression for the magnitude of the normal force Nw = µ_s•N

C) The largest distance up the ladder (d) max, d_max = 1.525 m

The friction is defined as when any  object slides on a surface then the force in opposite direction of the external applied force is generated which restrict the motion of the object is called as the friction force.

From the question, "smooth vertical wall" means that there is no friction there and thus the only vertical forces are the weights of the ladder and painter and the normal force at the floor.

a) Mass of ladder = 14 kg

Mass of painter = 8M = 8 * 14 = 112 kg

Thus, the magnitude of normal force is;

N = total mass x acceleration due to gravity = (14 + 112)9.8

N = 1236 N

(b) Sum of the moments about the base of the ladder:

ΣH = 0

Nw - µ_s•N = 0

Nw = µ_s•N

c) Since they are the only two horizontal forces in play, we know that

Nw = Ff where Ff is the friction force at the floor.

Ff = µ_s*N = 0.39 × 1236

Ff = 482.04 N

So, to find maximum distance painter can stand without slipping, we'll use the formula ;

[tex]N_{w}(Lsin\theta) = (Mgcos\theta)(\dfrac{L}{2}) + (8Mgcos\theta \times d_{max)[/tex]

Plugging in the relevant values, we have;

[tex]482.04(2.7\times sin55) = ((14 \times 9.8cos55)\times (\dfrac{2.7}{2})) + (8\times 14\times 9.8cos55 \times d_{max)[/tex]

[tex]1066.133 = 106.238 + 629.5575\times d_{max[/tex]

[tex]629.5575\times d_{max} = 1066.133 - 106.238[/tex]

[tex]d_{max} = \dfrac{959.895}{629.5575}[/tex]

d_max = 1.525 m

Thus, the magnitude of the normal force is  1236 N and an expression for the magnitude of the normal force Nw = µ_s•N . The largest distance up the ladder (d) max, d_max = 1.525 m

To know more about friction, follow

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Answer:

1) ΔQ₁ = 10.97 x 10³ J = 10.97 KJ

2) W₁ = 0 J

3) P = 41.66 x 10³ Pa = 41.66 KPa

4) v = 1618.72 m/s

5) ΔQ₂ = - 18.29 x 10³ J = - 18.29 KJ

6) W₂ = - 7.33 KJ

Explanation:

1)

The heat transfer for a constant volume process is given by the formula:

ΔQ₁ = ΔU = n Cv ΔT

where,

ΔQ₁ = Heat transfer during constant volume process

ΔU = Change in internal energy of gas

n = No. of moles = 4.4 mol

Cv = Molar Specific Heat at Constant Volume = 12.47 J/mol.k

ΔT = Change in Temperature = T₂ - T₁ = 500 k - 300 k = 200 k

Therefore,

ΔQ₁ = (4.4 mol)(12.47 J/mol.k)(200 k)

ΔQ₁ = 10.97 x 10³ J = 10.97 KJ

2)

Since, work done by gas is given as:

W₁ = PΔV

where,

ΔV = 0, due to constant volume

Therefore,

W₁ = 0 J

4)

The average kinetic energy of a gas molecule is given as:

K.E = (3/2)KT

but, K.E is also given by:

K.E = (1/2)mv²

Comparing both equations:

(1/2)mv² = (3/2)KT

mv² = 3KT

v = √(3KT/m)

where,

v = average speed of gas molecue = ?

K = Boltzman Constant = 1.38 x 10⁻²³ J/k

T = Absolute Temperature = 500 K

m = mass of a molecule = 7.9 x 10⁻²⁷ kg

Therefore,

v = √[(3)(1.38 x 10⁻²³ J/k)(500 k)/(7.9 x 10⁻²⁷ kg)]

v = 1618.72 m/s

3)

From kinetic molecular theory, we know that or an ideal gas:

P = (1/3)ρv²

where,

P = pressure of gas = ?

m = Mass of Gas = (Atomic Mass)(No. of Atoms)

m = (Atomic Mass)(Avogadro's Number)(No. of Moles)

m = (7.9 x 10⁻²⁷ kg/atom)(6.022 x 10²³ atoms/mol)(4.4 mol)

m = 0.021 kg

ρ = density = mass/volume = 0.021 kg/0.44 m³ = 0.0477 kg/m³

Therefore,

P = (1/3)(0.0477 kg/m³)(1618.72 m/s)²

P = 41.66 x 10³ Pa = 41.66 KPa

5)

The heat transfer for a constant pressure process is given by the formula:

ΔQ₂ =  n Cp ΔT

where,

ΔQ₂ = Heat transfer during constant pressure process

n = No. of moles = 4.4 mol

Cp = Molar Specific Heat at Constant Pressure = 20.79 J/mol.k

ΔT = Change in Temperature = T₂ - T₁ = 300 k - 500 k = -200 k

Therefore,

ΔQ₂ = (4.4 mol)(20.79 J/mol.k)(-200 k)

ΔQ₂ = - 18.29 x 10³ J = - 18.29 KJ

Negative sign shows heat flows from system to surrounding.

6)

From Charles' Law, we know that:

V₁/T₁ = V₂/T₂

V₂ = (V₁)(T₂)/(T₁)

where,

V₁ = 0.44 m³

V₂ = ?

T₁ = 500 K

T₂ = 300 k

Therefore,

V₂ = (0.44 m³)(300 k)/(500 k)

V₂ = 0.264 m³

Therefore,

ΔV = V₂ - V₁ = 0.264 m³ - 0.44 m³ = - 0.176 m³

Hence, the work done , will be:

W₂ = PΔV = (41.66 KPa)(- 0.176 m³)

W₂ = - 7.33 KJ

Negative sign shows that the work is done by the gas

Answer:

A) N = (M + mf + md) g

B) d = md L / (2 mf)

Explanation:

Draw a free body diagram.  There are four forces acting on the board.

Weight force M g pulling down at the center of the board.

Normal force N pushing up at the center of the board.

Weight force mf g pulling down a distance d from the center.

Weight force md g pulling down at the end of the board.

Sum of forces in the y direction:

∑F = ma

N − M g − mf g − md g = 0

N = (M + mf + md) g

Sum of moments about the center of the board:

∑τ = Iα

md (L/2) − mf d = 0

d = md L / (2 mf)

The magnitude of the upward force n exerted by the support on the board will be the same with the magnitude of the weight of the seesaw. Which is

W = 9.8M Newton

The father should sit at L/4 at the other end in order to balance the system at rest

Since the seesaw is of a uniform board, the center of gravity will act at the center. If it is of length L, the support called the fulcrum will be positioned at L/2.

If the daughter is a distance L/2 from the center, Then, she must be positioned at L/4 from the one edge of the board.

A. The magnitude of the upward force n exerted by the support on the board will be the same with the magnitude of the weight of the seesaw. Which is

W = mg

W = 9.8M Newton

The weight of both the father and the daughter will act downward. so, they will not be included.

The father should sit at L/4 at the other end in order to balance the system at rest

Learn more here: https://brainly.com/question/15651723

Answer:

Explanation:

TJVFKBFVN

Complete Question:

Check the file attached to get the complete question

Answer:

In the film Ice word Revenge, vehicle 2 did not fall of the cliff because, [tex]Weight_{vehicle 1} < Weight_{vehicle 2}[/tex] but in Claire's test, vehicle 2 off the cliff because [tex]Weight_{vehicle 1} \geq Weight_{vehicle 2}[/tex]

Explanation:

In Claire's test, the weight of vehicle 1 is either equal to or greater than the weight of vehicle 2, so it was sufficient to push it down the cliff.  In the film Ice word revenge, the weight of vehicle 1 is less than the weight of vehicle 2, it is not sufficient to make it fall off the cliff ( Note: Looking exactly the same in the movie, as Claire claimed, does not mean they have the same mass). Therefore if Claire wants a collision that will not make the vehicle 2 fall off the cliff, he should collide it with a vehicle of lesser mass/weight.

Answer:

no the answer was both friction and mass

Explanation:

The reason that Vehicle 2 fell off the cliff in Claire's test of the collision scene, but Vehicle 2 did not fall off the cliff in the film Iceworld Revenge is because of the friction and mass. A different friction, called foam, is used in Claire's test. The foam has a really low friction that caused vehicle 2 to fall from the cliff. According to evidence card B which states that, “In Iceworld Revenge, Vehicle 2 moves slowly toward the cliff after the collision, halting only before it goes over the side. In Clair's test, Vehicle 2 went over the cliff at full speed”.This evidence confirms my arguments that in the film, vehicle 2 did not drive as quickly as in the film scene of Claire.

Answer:

Both of Arnell and Adeen are right.

Explanation:

For Adeen, hammering the wire makes it flat, effectively reducing the cross sectional area, and increasing the length of the wire. Recall that the resistivity of a metal conductor increases with length and decreases with cross sectional area. From this, we can see that the resistance of the wire will increase due to the hammering. This means Adeen is correct.

For Arnell, heating a metal causes the atoms along with their electrons to vibrate in a random manner. These random motions is not organised and can be in any direction. For electricity to flow smoothly, the electrons must travel in the same direction in an orderly fashion. The randomly vibrating atoms will continuously bump into the flowing electron, resisting the smooth motion of the electrons. This collisions results in an additional resistance, hence, the resistance is increased. This means Arnell is correct.

Answer:

dY/dt = k(Y - Ys).

Explanation:

Okay, this question based on the law known as the Newton's law of cooling. According to Newton's law of cooling, when an object is placed into a specific or particular environment, the object's temperature will definitely be lower than the temperature of the surrounding or the environment.

So, we are given that the temperature of the object = 38 degree F = Y(o) of the object and the temperature of the environment = 68 degree F = Ys

Hence, dY/dt = k(Y - Ys).

dY/ (Y - Ys) =kdt.

Answer:

False

Explanation:

False, as a magnetic field is generated whenever current travels through a conductor.

An electromagnet consists of a coil of wire wrapped around a bar of iron. The coil and iron bar get magnetized when electric current flows through the wire. An electromagnet also has north and south magnetic poles. The magnetic field is strongest at either pole of the magnet.

Answer:

1- Short circuit

2- ammeter

Answer:

The axial region of the body consists of the bones of the head, trunk of a vertebrate, skull, vertebral column, and thoracic cage. The human skeleton consists of 80 bones.

Explanation:

The axial region of the body consists of the bones of the head, trunk of a vertebrate, skull, vertebral column, and thoracic cage. The human skeleton consists of 80 bones.

It is composed of the following six parts:

1. Skull (22 bones)

2. Ossicles of the middle ear

3. Hyoid bone

4. Rib cage

5. Sternum

6. Vertebral column

The axial region of the body forms the vertical axis of the body as the axial skeleton supports the head, neck, back, and chest.

Answer:

The environment is warmed by the light throughout the day, such that the temperature increases. The weather is decreasing and the temperature decreases in the night as the sun falls. There was a misunderstanding. Thanks to the density, the atmosphere becomes densest on the earth. The air becomes colder and colder when you move up.

Explanation:

Answer is above

Hope this helps.

Answer:

A) Arrangement A

Explanation:

The rate of heat conduction is given by Fourier's Law of Heat Conduction. It is given as follows:

Q = KAΔT/L

where,

Q = Rate of Heat Transfer or Conduction

K = Thermal Conductivity

A = Cross-Sectional Area

ΔT = Difference in Temperature

L = Thickness

So, it is clear from the formula that for a constant temperature difference and value of thermal conductivity, the rate of heat transfer is directly proportional to the cross-sectional area and it is inversely proportional to the thickness.

Therefore, the arrangement with larger cross-sectional area and smaller thickness will be the one with the greatest heat transfer rate and as a result greatest heat shall be conducted through that arrangement.

It is clear that the parallel arrangement that is arrangement A, has higher cross-sectional area and smaller thickness. Therefore, the correct option is:

A) Arrangement A

Answer:

a) the velocity increases then decreases.

Answer:

E = 0.0130 V/m.

Explanation:

The electric field is related to the potential difference as follows:

[tex] E = \frac{\Delta V}{d} [/tex]

Where:

E: is electric field

ΔV: is the potential difference = 3.95 mV  

d: is the distance of a person's chest = 0.305 m

Then, the electric field is:

[tex]E = \frac{\Delta V}{d} = \frac{3.95 \cdot 10^{-3} V}{0.305 m} = 0.0130 V/m[/tex]

Therefore, the maximum electric field created is 0.0130 V/m.

I hope it helps you!

Explanation:

It is given that,

The separation between two parallel wires, r = 5.6 cm = 0.056 m

Current in both the wires is 2.65 A

(a) We need to find the magnitude of the force per unit length between the wires. It can be given by :

[tex]\dfrac{F}{l}=\dfrac{\mu_o I_1I_2}{2\pi r}\\\\\dfrac{F}{l}=\dfrac{4\pi \times 10^{-7}\times 2.65\times 2.65}{2\pi \times 0.056}\\\\\dfrac{F}{l}=2.5\times 10^{-5}\ N/m[/tex]

(b) As the current is in same direction, the wires will attract each other.

Answer:

20.0 mph

Explanation:

Let x represent the speed in still air, and t represent the time of flight;

Speed of wind = 2 mph

When flying with the wind, it's Speed is;

x + 2

When flying against wind, it's speed is;

x - 2

distance = speed × time;

When flying with the wind, distance is;

(x+2)t = 88 .....1

When flying against wind, distance is;

(x-2)t = 72 .......2

Solving the simultaneous equation;

Divide equation 1 by 2

(x+2)t/(x-2)t = 88/72

(x+2)/(x-2) = 1.222

x+2 = 1.222(x-2)

x+2 = 1.222x - 2.444

x(1.222-1) = 2+2.444

x(0.222) = 4.444

x = 4.444/0.222

x = 20.0 mph

the rate of the bird in still​ air is 20.0 mph

Answer:

  see below for the truth table

Explanation:

Truth Table

As we will see from the description of operation, any input low causes the output to be high. This is the logic of a NAND gate. The truth table is attached.

Working Principle

Pulling any of A, B, or C low will saturate transistor Q1, depriving Q2 of any base current, cutting it off. Then Q5 is also deprived of base current and is cut off. Meanwhile, the current through R2 supplies base current to Q4, allowing it to pull the output high.

If all of A, B, and C are high (or open), base current is supplied to Q2 through the base-collector junction of Q1. Then Q2 saturates, supplying base current to Q3. Diode D1 ensures that the voltage across Q2 will be insufficient to supply any base current to Q4, so it stays cut off.

Complete Question

A small block is released from rest at the top of a frictionless incline. The distance from the top of the incline to the bottom, measured along the incline, is 3.40 m. The vertical distance from the top of the incline to the bottom is 1.09 m. If [tex]g=9.8 \ m/s^2[/tex] , what is the acceleration of the block as it slides down the incline plane

Answer:

The acceleration is  [tex]a = 3.142 m/s^2[/tex]

Explanation:

From the question we  are told that

The distance from top to bottom of the inclined plane measured along the incline  is [tex]d = 3.40 \ m[/tex]

The distance from top to bottom of the inclined plane  measured along the vertical axis is  

         [tex]D = 1.90 \ m[/tex]

According to the SOHCAHTOA rule

        [tex]sin \theta = \frac{D}{d}[/tex]

=>      [tex]\theta = sin ^{-1} [\frac{D}{d} ][/tex]

substituting values

=>         [tex]\theta = sin ^{-1} [\frac{1.09}{3.40} ][/tex]

            [tex]\theta = 18.699^o[/tex]T

The acceleration of a block on a frictionless inclined plane is mathematically represented as

            [tex]a = gsin \theta[/tex]

substituting values

           [tex]a = 9.8 * sin(18.699)[/tex]

         [tex]a = 3.142 m/s^2[/tex]

Answer:

v= 0.94 m/s

Explanation:

In order to calculate the speed of the waves, you use the following formula for the speed of the waves:

[tex]v=\lambda f[/tex]          (1)

v: speed of the wave

λ: wavelength of the wave

f: frequency of the wave

The frequency is calculated by using the information about the time that boat takes to travel from its highest point to its lowest point. This time is a half of a period:

[tex]\frac{T}{2}=3.5s\\\\T=7.0s[/tex]

Then, the frequency is:

[tex]f=\frac{1}{T}=\frac{1}{7s}=0.142Hz[/tex]  

The wavelength of the wave is the distance between crests of the wave

[tex]\lambda=6.6m[/tex]

With the values of the frequency and the wavelength, you can find the speed of the wave by using the equation (1):

[tex]v=(6.6m)(0.142Hz)=0.94\frac{m}{s}[/tex]

The speed of the wave is 0.94m/s

Answer:

The volume is  [tex]V =5.32 *10^{-5} \ m^3[/tex]

Explanation:

From the question we are told that

    The power of the heating element is [tex]P = 2.0 kW = 2.0 *10^3 \ W[/tex]

    The temperature of the water in the kettle is  [tex]T _w = 100^oC[/tex]

     The time to convert water to steam is t = 1 minute = 60 sec

      The specific latent heat of vaporization is [tex]H_v = \ 2,257,000 J/kg[/tex]

      The density of water is [tex]\rho_w = 1000\ kg/m^3[/tex]

The power of the heating element is mathematically represented as

      [tex]P = \frac{E}{t}[/tex]

Where E  Energy generated by the heating element in term of heat

      [tex]E = Pt[/tex]

substituting values

      [tex]E = 2.0 *10^{3} * 60[/tex]

      [tex]E = 120000 J[/tex]

Now

 The latent heat of vaporization is mathematically represented as

         [tex]H_v = \frac{E}{m}[/tex]

Where m is the mass of water converted to steam

 So

      [tex]m = \frac{E}{H_v}[/tex]

substituting values

      [tex]m = \frac{120000}{2257000}[/tex]

     [tex]m = 0.0532\ kg[/tex]

The volume of water converted to steam is mathematically evaluated as

    [tex]V = \frac{m }{\rho_w}[/tex]

substituting values

   [tex]V = \frac{0.0532}{1000}[/tex]

    [tex]V =5.32 *10^{-5} \ m^3[/tex]

Answer:

The time taken by the sound is [tex]3.82\times 10^{-4}\ s[/tex]

Explanation:

We have,

A low-frequency sound source is placed to the right of a person, whose ears are approximately 13 cm apart, and the speed of sound generated is 340 m/s.

It is required to find the time taken by the sound when the sound arrives at the right ear and the sound arrives at the left ear. Let t is the time taken. It can be calculated as :

[tex]v=\dfrac{d}{t}\\\\t=\dfrac{d}{v}\\\\t=\dfrac{0.13}{340}\\\\t=3.82\times 10^{-4}\ s[/tex]

So, the time taken by the sound is [tex]3.82\times 10^{-4}\ s[/tex]

Answer:

B: The electromagnetic waves reach earth, while the mechanical waves do not.

correct Answer:

The electromagnetic waves reach Earth, while the mechanical waves do not

Answer:

a. 6666.67 V/m

b. 2. the positively charged plat

Explanation:

a. The computation of the magnitude of the electric field between the plates is shown below:

As we know that

[tex]E = \frac{V}{d}[/tex]

[tex]= \frac{400 V}{0.06 m}[/tex]

= 6666.67 V/m

hence, the magnitude of the electric field is 6666.67 V/m

b. Based on this the higher potential is positively charged plate as the flow of the current goes from positive to negative and it is inverse in case of th electron

We simply applied the above formula  

Answer:

The weight at a distance 2 RE from surface of earth is W/9

Explanation:

For the value of acceleration due to gravity (g), we have a formula, that is:

g = (G)(ME)/(RE)²    ----- equation (1)

where,

G = Gravitational Constant

ME = Mass of Earth

RE = Radius of Earth

g = Acceleration due to gravity on surface of earth = 9.8 ms²

When the person goes 2RE, distance above earth's surface. Then the total distance from center of earth becomes: 2RE + RE = 3RE.

Therefore, equation (1) becomes:

gh = (G)(ME)/(3RE)²

where,

gh = acceleration due to gravity at height

gh = (G)(ME)/(RE)²9

using equation (1), we get:

gh = g/9

Now, he weight is given by formula:

W = mg   ------- equation (2)

At height 2RE

Wh = (m)(gh)

where,

Wh = Weight at height = ?

m = mass of astronaut

Therefore, using vale of gh, we get:

Wh = mg/9

Using equation (2), we get:

Wh = W/9

Answer:

1) 2.9m/s

2)0.235cm

3)0.509s

Explanation:

1. moments are conserved, when the steak hits the pan:

velocity 'v' of the steak:  

v = √(2gh) = √(2*9.81*0.5) = 3.13 m/s

velocity pan + steak is

v =[tex]m_1v_1/(m_1+m_2)[/tex]= 2.5*3.13/(2.7) = 2.9 m/s

2.initial kinetic energy of pan + steak = spring energy  

1/2 mv² = 1/2 kA²  

where, A = amplitude  

2.7 x 2.9² = 410 x A²

A²=22.707/410

A = 0.235 cm

3. T = 2π√(m/k) = 2π√(2.7/410) = 0.509 s

Therefore, the period of that motion is 0.509s

1) The speed of the pan and steak immediately after the collision is 2.9m/s

2) The  amplitude of the subsequent motion is 0.235cm.

3) The period of that motion is 0.509s.

1.

Since

v = √(2gh) = √(2*9.81*0.5) = 3.13 m/s

Also,

v == 2.5*3.13/(2.7)

= 2.9 m/s

2.

Now

initial kinetic energy of pan + steak = spring energy  

So,

1/2 mv² = 1/2 kA²  

Here,

A = amplitude  

2.7 x 2.9² = 410 x A²

A²=22.707/410

A = 0.235 cm

3.

Now

T = 2π√(m/k)

= 2π√(2.7/410)

= 0.509 s

Learn more about speed here: https://brainly.com/question/14628211

A very small source of light that radiates uniformly in all directions produces an electric field with an amplitude of ܧ ௠at a distance R from the source. What is the amplitude of the magnetic field at a point 2R from the source?

If the distance from the source is doubled. The amplitude of the magnetic field is smaller 4 times.

Answer:

Explanation:

(a)

  [tex]\dfrac{6.2\cdot 10^2\,\text{rev}}{60\,\text{s}}\times\dfrac{2\pi\,\text{rad}}{\text{rev}}=\dfrac{62\pi\,\text{rad}}{3\,\text{s}}\approx\boxed{64.93\,\text{rad/s}}[/tex]

__

(b)

  [tex]d=r\theta=(3.0\,\text{m})(2.0\cdot 10^2\,\text{s})\left(\dfrac{62\pi\,\text{rad}}{3\,\text{s}}\right)=124\pi\cdot 10^2\,\text{m}=\boxed{38\,956\,\text{m}}[/tex]

Answer:

Probably just enforcing it little by little. (If you mean a habit. If you mean a certain topic it's different.)

Explanation:

If you are trying to teach your students a habit-

Try to correct them everytime they don't follow it. Expect them to do so and give a reward when they earn it.

If you mean a certain topic-

Make a slideshow or a presentation with an interactive game. Making it not boring and having them more attentive.

I gave a more general answer, so if you would like to go deeper into the subject I would be more happy to.

(If this helped, please let me know. If you have any questions do not be afriad to ask!)

Answer:

The force of gravity at the shell will be extremely great on me due to the huge mass collapsed into the small radius.

At the center of the shell, the gravitational forces all around should cancel out, giving me a feeling of weightlessness; which will be a lesser force compared to that felt while standing on the shell.

Explanation:

For the collapsed earth:

mass = 5.972 × 10^24 kg

radius = 1 ft

according to Newton's gravitation law, the force of gravity due to two body with mass is given as

Fg = GMm/[tex]R^{2}[/tex]

Where Fg is the gravitational force between the two bodies.

G is the gravitational constant

M is the mass of the earth

m is my own mass

R is the distance between me and the center of the earths in each case

For the case where I stand on the shell:

radius R will be 1 ft

Fg = GMm/[tex]1^{2}[/tex]

Fg = GMm

For the case where I stand stand inside the shell, lets say I'm positioned at the center of the shell. The force of gravity due to my mass will be balanced out by all other masses around due to the shell of the hollow earth. This cancelling will produce a weightless feeling on me.

Answer:

h = 14.4 m

Explanation:

The height can be calculated by energy conservation:

[tex] K_{r} + K_{t} - W = E_{p} [/tex]

Where:      

W: is the work

[tex]E_{p}[/tex]: is the potential energy

[tex]K_{r}[/tex]: is the rotational kinetic energy  

[tex]K_{t}[/tex]: is the transitional kinetic energy

Initially, the wheel has rotational kinetic energy and translational kinetic energy, and then when stops it has potential energy.  

[tex] K_{r} + K_{t} - W = E_{p} [/tex]

[tex] \frac{1}{2}I\omega_{0}^{2} + \frac{1}{2}mv^{2} - W = mgh [/tex]

Where:                                            

I: is the moment of inertia = 0.800 mr²

ω₀: is the angular speed = 25.0 rad/s

m: is the mass = P/g = 397 N/9.81 m*s⁻² = 40.5 kg

v: is the tangential speed = ω₀r²            

Now, by solving the above equation for h we have:                        

[tex] h = \frac{\frac{1}{2}(I\omega_{0}^{2} + mv^{2}) - W}{mg} [/tex]  

[tex] h = \frac{\frac{1}{2}(I\omega_{0}^{2} + m(\omega_{0}*r)^{2}) - W}{mg} [/tex]

[tex] h = \frac{\frac{1}{2}(0.800*40.5 kg*(0.600 m)^{2}*(25.0 rad/s)^{2} + 40.5 kg*(25.0 rad/s*0.600 m)^{2}) - 2500 J}{40.5 kg*9.81 m/s^{2}} = 14.4 m [/tex]

Therefore, the height is 14.4 m.

I hope it helps you!