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Gelneren [198K]

3 years ago

7

How tall is Mount Everest?

2 answers:

nikklg [1K]3 years ago

6 0

Answer: 29,035 feet

Explanation:

White raven [17]3 years ago

3 0

Answer:

29,032′

Explanation:

You might be interested in

Why are water storage tanks usually placed on high towers

sammy [17]

Thay are on high towers because if it was below how would the water flow. Putting it on high towers gives you an advantage of the gravity with means you got free pressure without having to use a pump.

<span>Water pressure = Height * density * gravity</span>

7 0

3 years ago

Read 2 more answers

The interior space of large box is kept at 30 C. The walls of the box are 3 m high and have a ‘sandwich’ construction consisting

White raven [17]

Answer:

$\frac{\dot Q}{A} =20.129\ W.m^{-2}$

$T_1=27.58\ ^{\circ}C$ & $T_2=2.41875\ ^{\circ}C$

Explanation:

Given:

interior temperature of box, $T_i=30^{\circ}C$

height of the walls of box, $h=3\ m$

thickness of each layer of bi-layered plywood, $x_p=1.25\ cm=0.0125\ m$

thermal conductivity of plywood, $k_p=0.104\ W.m^{-1}.K^{-1}$

thickness of sandwiched Styrofoam, $x_s=5\ cm=0.05\ m$

thermal conductivity of Styrofoam, $k_s=0.04\ W.m^{-1}.K^{-1}$

exterior temperature, $T_o=0^{\circ}C$

<u>From the Fourier's law of conduction:</u>

$\dot Q=\frac{dT}{(\frac{x}{kA}) }$

$\dot Q=\frac{dT}{R_{th} }$ ....................................(1)

<u>Now calculating the equivalent thermal resistance for conductivity using electrical analogy:</u>

$R_{th}=R_p+R_s+R_p$

$R_{th}=\frac{x_p}{k_p.A}+\frac{x_s}{k_s.A}+\frac{x_p}{k_p.A}$

$R_{th}=\frac{1}{A} (\frac{x_p}{k_p}+\frac{x_s}{k_s}+\frac{x_p}{k_p})$

$R_{th}=\frac{1}{A} (\frac{0.0125}{0.104}+\frac{0.05}{0.04}+\frac{0.0125}{0.104})$

$R_{th}=\frac{1.4904}{A}$ .....................(2)

Putting the value from (2) into (1):

$\dot Q=\frac{30-0}{\frac{1.4904}{A} }$

$\dot Q=\frac{30\ A}{1.4904}$

$\frac{\dot Q}{A} =20.129\ W.m^{-2}$ is the heat per unit area of the wall.

The heat flux remains constant because the area is constant.

<u>For plywood-Styrofoam interface from inside:</u>

$\frac{\dot Q}{A} =k_p.\frac{T_i-T_1}{x_p}$

$20.129=0.104\times \frac{30-T_1}{0.0125}$

$T_1=27.58\ ^{\circ}C$

&<u>For Styrofoam-plywood interface from inside:</u>

$\frac{\dot Q}{A} =k_s.\frac{T_1-T_2}{x_s}$

$20.129=0.04\times \frac{27.58-T_2}{0.05}$

$T_2=2.41875\ ^{\circ}C$

4 0

3 years ago

The Burj Khalifa in Dubai is the world's tallest building. The structure is 828 m (2,716.5 feet) and has more than 160 stories.

Elena L [17]

Answer:

h = 599.5 m

Explanation:

Given,

height of structure = 828 m

weight of the tourist = 184 lb

= 184 x 0.45359 = 83.43 Kg

Potential energy = 187000 J

PE = m gd

$d = \frac{PE}{mg}$

$d = \frac{187000}{83.43\times 9.81}$

h = 228.5 m

Height of the room above the ground.

h = 828 - 228.5

h = 599.5 m

Height of the floor above ground is equal to 599.5 m.

4 0

3 years ago

Which of the following is an impact of trampling of beach grass by humans and vehicles?

grigory [225]

Increase in sea water pollution

6 0

3 years ago

A skater starts on a ramp 5 m above the ground. They have a mass of 45 kg. What is their gravitational potential energy?

Licemer1 [7]

Answer:

2205J

Explanation:

45 x 5 x 9.8 = 2205

5 0

3 years ago