35 points an brainiest if correct

What are the advantages and disadvantages of a mine heardgear

Irina18 [472]

Answer:

If there is a shaft with headgear, then mining can take place until that depth of the shaft. If it is accessed horizontal Adits, it can mine until the lowest Adit from upwards. If it is accessed decline, the development and mining can continue so long as economic exploitation is possible.

Explanation:

What are the disadvantages of mining headgear? They totally cut off your vision of anything above your head. They are hot, most of the time

7 0

2 years ago

1. A rectangular fish tank measures 1.5 meters by 2 meters by 20 cm. When it is filled with water, how many kilograms will the w

chubhunter [2.5K]

20kg I’m pretty sure

7 0

3 years ago

Define the Artist class in Artist.py with a constructor to initialize an artist's information. The constructor should by default

Sunny_sXe [5.5K]

Answer:

Explanation:

As a result of the codes used to making this solved, i was unable to upload my answer, therefore i'm sending a screenshot of the codes.

thank you for your understanding,

cheers i hope this helps

5 0

3 years ago

134a refrigerant enters an adiabatic compressor at 140kPa and -10C, the refrigerant is compressed at 0.5kW up to 700kPa and 60C.

vichka [17]

Answer:

(a) 65.04%

(b) 16.91%

Solution:

As per the question:

At inlet:

Pressure of the compressor, P = 140 kPa

Temperature, T = $- 10^{\circ}C$ = 263 K

Isentropic work, W = 700 kPa

At outlet:

Pressure, P' = 700 kPa

Temperature, T' = $60^{\circ}C$ = 333 K

Now, from the steam table;

At the inlet , at a P = 700 kPa, T = $60^{\circ}C$ :

h = 243.40 kJ/kg, s = 0.9606 kJ/kg.K

At outlet, at P = 140 kPa, T = $- 10^{\circ}C$ :

h' = 296.69 kJ/kg, s' = 1.0182 kJ/kg.K

Also in isentropic process, s = $s'_{s}$ and $h'_{s} = 278.06 kJ/kg.K$ at 700kPa

(a) Isentropic efficiency of the compressor, $\eta_{s} = \frac{Work\ done\ in\ isentropic\ process}{Actual\ work\ done}$

$\eta_{s} = \frac{h'_{s} - h}{h' - h} = frac{278.06 - 243.40}{296.69 - 243.40} = 0.6504 = 65.04%$

(b) The temperature of the environment, $T_{e} = 27^{\circ}C$ = 273 + 27 = 300 K

Availability at state 1, $\Psi = h - T_{e}s = 243.40 - 300\times 0.9606 = - 44.78 kJ/kg$

Similarly for state 2, $\Psi' = h' - T_{e}s' = 296.69 - 300\times 1.0182 = - 8.77 kJ/kg$

Now, the efficiency of the compressor as per the second law;

$\eta' = \frac{\Psi' - \Psi}{h' - h} = \frac{- 8.77 - (- 44.78)}{296.69 - 243.40} = 0.6757$ = 67.57%

4 0

4 years ago

Write a program that computes the square footage of a house given the dimensions of each room.Have the program ask the user how

baherus [9]

#include

int main () {

printf("Program to calculate the square footage of the house.\n");

int total_rooms;

double length, width;

double total_square_footage = 0.0;

printf("Enter total number of rooms in the house:");

scanf("%d", &total_rooms);

for (int i = 0; i
printf("Enter the lenght and width of room %d: ", i+1);

scanf("%if %if", &lenght, &width);

total_square_footage += lenght*width;

}

printf("Total square footage of the house: %if\n", total_square_footage);

return 0;

}

Please mark it as brainliest answer:).

4 0

3 years ago