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nadezda [96]
2 years ago
11

Three natural materials that were used by early man as roof covering​

Engineering
2 answers:
olga55 [171]2 years ago
8 0

Explanation:

animal parts, wood, rock, and clay

Law Incorporation [45]2 years ago
8 0

Answer:

roofing sheet

wood

metal

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Which statement best describes how a hearing aid works?
Verizon [17]

The following statement best describes how a hearing aid works, An implant bypasses parts of the cochlea and sends messages to the brain, where they are then recognized as sound.

Explanation:

  • The hearing aid works as An implant bypasses parts of the cochlea and sends messages to the brain, where they are then recognized as sound.
  • A hearing aid is a device designed to improve hearing by making sound audible to a person with hearing loss.
  • Modern devices uses all sophisticated digital signal processing to try and improve the speech understanding, intelligibility and comfort for the user, such as signal processing
  • Almost all hearing aids in use in the US are digital hearing aids Devices similar to hearing aids include cochlear implant.
  • Early devices, such as ear trumpets or ear horns, were the passive amplification cones which were designed to gather the sound energy and directly goes into the ear canal.
  • Most common issues with hearing aid fitting and use are the occlusion effect, loudness recruitment, and understanding speech in noise.

4 0
3 years ago
Steam flows steadily through an adiabatic turbine. The inlet conditions of the steam are 10 MPa, 450°C, and 80 m/s, and the exit
8090 [49]

Answer:

a) The change in Kinetic energy, KE = -1.95 kJ

b) Power output, W = 10221.72 kW

c) Turbine inlet area, A_1 = 0.0044 m^2

Explanation:

a) Change in Kinetic Energy

For an adiabatic steady state flow of steam:

KE = \frac{V_2^2 - V_1^2}{2} \\.........(1)

Where Inlet velocity,  V₁ = 80 m/s

Outlet velocity, V₂ = 50 m/s

Substitute these values into equation (1)

KE = \frac{50^2 - 80^2}{2} \\

KE = -1950 m²/s²

To convert this to kJ/kg, divide by 1000

KE = -1950/1000

KE = -1.95 kJ/kg

b) The power output, w

The equation below is used to represent a  steady state flow.

q - w = h_2 - h_1 + KE + g(z_2 - z_1)

For an adiabatic process, the rate of heat transfer, q = 0

z₂ = z₁

The equation thus reduces to :

w = h₁ - h₂ - KE...........(2)

Where Power output, W = \dot{m}w..........(3)

Mass flow rate, \dot{m} = 12 kg/s

To get the specific enthalpy at the inlet, h₁

At P₁ = 10 MPa, T₁ = 450°C,

h₁ = 3242.4 kJ/kg,

Specific volume, v₁ = 0.029782 m³/kg

At P₂ = 10 kPa, h_f = 191.81 kJ/kg, h_{fg} = 2392.1 kJ/kg, x₂ = 0.92

specific enthalpy at the outlet, h₂ = h_1 + x_2 h_{fg}

h₂ = 3242.4 + 0.92(2392.1)

h₂ = 2392.54 kJ/kg

Substitute these values into equation (2)

w = 3242.4 - 2392.54 - (-1.95)

w = 851.81 kJ/kg

To get the power output, put the value of w into equation (3)

W = 12 * 851.81

W = 10221.72 kW

c) The turbine inlet area

A_1V_1 = \dot{m}v_1\\\\A_1 * 80 = 12 * 0.029782\\\\80A_1 = 0.357\\\\A_1 = 0.357/80\\\\A_1 = 0.0044 m^2

3 0
3 years ago
Comparación de hipotecas Los Chos
aleksklad [387]

Answer:

I don't understand the language French sorry can't answer

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3 years ago
Joe is a chemical engineer whose plant discharges heavy metals into the local river. By the test authorized by the city governme
chubhunter [2.5K]

Answer:

B probably

Explanation:

Because the prompt doesn't specify what sort of violation it could be anything maybe when they release the metals during the day and so on.

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For powder compaction using a single-action punch, derive an expression for the distribution of axial pressure within a die of r
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a) 2∪p/lb (l+b)dH

b) po exp( 4∪x/l)

Explanation:

please check the attachment for proper explanation and proper sign notations thanks.

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