A red circle and diagonal slash on a sign means that:.

Hot air at an average temperature of 100 degC flows through a 3 m long tube with an inside diameter of 60 mm. The temperature of

Arte-miy333 [17]

Answer:

$\dot Q = 912.017\,W$

Explanation:

The heat transfer rate due to convection is calculated by this formula:

$\dot Q = h_{air}\cdot A_{tube, in}\cdot (T_{air} - T_{tube})$

The output is determined by replacing terms:

$\dot Q = (20.1\,\frac{W}{m^{2}\cdot ^{\textdegree}C})\cdot (\pi )\cdot (0.06\,m)\cdot (3\,m)\cdot (100^{\textdegree}C-20^{\textdegree}C)$

$\dot Q = 912.017\,W$

6 0

3 years ago

Read 2 more answers

A rotator has a weight of 100lb with a centroidal radius of gyration of 9 in. Determine the moment of inertia about the center o

Ronch [10]

Answer:

8100 lbin²

Explanation:

Moment or inertia is expressed using the formula

I = mr²

M is the mass of the body

r is the radius of gyration

Given

W = 100lb

r = 9in

Required

Moment of inertia

I = Wr²

I = 100(9)²

I = 100×81

I = 8100lbin²

Hence the moment of inertia about the center of gravity for the rotator is

8100 lbin²

8 0

3 years ago

The natural material in a borrow pit has a mass unit weight of 110.0 pcf and a water content of 6%, and the specific gravity of

enot [183]

Answer:

A. 288,030.91 cy

B. The amount of water that must be removed from the natural material is 483541.04254 gallons of water

Explanation:

The natural material in the barrow properties are;

The mass unit weight, γ = 110.0 pcf

The water content, w = 6%

The specific gravity of the soil solids, $G_s$ = 2.63

The desired dry unit weight, $\gamma _d$ = 122 pcf

The water content, w₁ = 5.5 %

The net section volume, $V_T$ = 245,000 cy = 6,615,000 ft³

A. $\gamma _d$ = $W_s$ / $V_T$

∴ $W_s$ = $V_T$ × $\gamma _d$ = 6,615,000 ft³ × 122 lb/ft³ = 807030000 lbs

w = ( $W_w$ / $W_s$ ) × 100

∴ $W_w$ = (w/100) × $W_s$ = (6/100) × 807030000 lbs = 48421800 lbs

The weight of solids

W = $W_s$ + $W_w$ = 807030000 lbs + 48421800 lbs = 855451800 lbs

V = W/γ = 855451800 lbs/(110.0 lb/ft.³) = 7776834.54545 ft.³ = 288,030.91 cy

V = 288,030.91 cy

The amount of cubic yards of borrow required = 288,030.91 cy

B. The volume of water in the required soil is found as follows;

$W_{w1}$ = (w₁/100) × $W_s$ = (5.5/100) × 807030000 lbs = 44386650 lbs

The amount of water that must be added = $W_{w1}$ - $W_w$ = 44386650 lbs - 48421800 lbs = -4,035,150 lbs

Therefore, 4,035,150 lbs of water must be removed

The density of water, ρ = 8.345 lbs/gal

Therefore, V = 4,035,150 lbs/(8.345 lbs/gal) = 483541.04254 gal of water must be removed from the natural material

7 0

3 years ago

A lake is fed by a polluted stream and a sewage outfall. The stream and sewage wastes have a decay rate coefficient (k) of 0.5/d

joja [24]

Solution :

Given :

k = 0.5 per day

$C_s = 10 \ mg/L \ ; \ \ Q_s= 40 \ m^3/s$

$C_{sw} = 100 \ ppm \ ; \ \ Q_{sw}= 0.5 \ m^3/s$

Volume, V $= 200 \ m^3$

Now, input rate = output rate + KCV ------------- (1)

Input rate $= Q_s C_s + Q_{sw}C_{sw}$

$=(40 \times 10) + (0.5\times 100)$

$= 2 \times 10^5 \ mg/s$

The output rate $= Q_m C_{m}$

= ( 40 + 0.5 ) x C x 1000

$=40.5 \times 10^3 \ C \ mg/s$

Decay rate = KCV

∴ $KCV =\frac{0.5/d \times C \ \times 200 \times 1000}{24 \times 3600}$

= 1.16 C mg/s

Substituting all values in (1)

$2 \times 10^5 = 40.5 \times 10^3 \ C+ 1.16 C$

C = 4.93 mg/L

4 0

3 years ago

Electrical strain gauges were applied to a notched specimen to determine the stresses in the notch. The results were εx=0.0019 a

pickupchik [31]

Answer:

$\sigma_x=451.8MPa$

$\sigma_y=265.99MPa$

Explanation:

$\varepsilon _x=0.0019$

$\varepsilon _y=0.00072$

Poission's ratio for steel =0.28

We know that

$\varepsilon _x=\dfrac{\sigma _x}{E}-\mu\dfrac{\sigma _x}{E}$

$\varepsilon _y=\dfrac{\sigma _y}{E}-\mu\dfrac{\sigma _x}{E}$

Now by putting the values

$0.0019=\dfrac{\sigma _x}{200\times 1000}-0.28\dfrac{\sigma _y}{200\times 1000}$

$0.00072=\dfrac{\sigma _y}{200\times 1000}-0.28\dfrac{\sigma _x}{200\times 1000}$

So $\sigma_x=451.8MPa$

$\sigma_y=265.99MPa$

6 0

4 years ago