Answer:
I think D is the correct answer.
Explanation:
hope its correct
IV. An annealed copper strip 9 inches wide and 2.2 inches thick, is rolled to its maximum possible draft in one pass. The following properties of annealed copper are given: strength coefficient is 90,000 psi; true strain at the onset of non-uniform deformation is 0.45; and, engineering strain at yield is 0.11. The coefficient of friction between strip and roll is 0.2. The roll radius is 14inches and the rolls rotate at 150 rpm. Calculate the roll-strip contact length. Calculate the absolute value of thetrue strain that the strip undergoes in this operation. Determine the average true stress of the strip in theroll gap. Calculate the roll force. Calculate the horsepower required.
Answer:
13.9357 horse power
Explanation:
Annealed copper
Given :
Width, b = 9 inches
Thickness, [tex]$h_0=2.2$[/tex] inches
K= 90,000 Psi
μ = 0.2, R = 14 inches, N = 150 rpm
For the maximum possible draft in one pass,
[tex]$\Delta h = H_0-h_f=\mu^2R$[/tex]
[tex]$=0.2^2 \times 14 = 0.56$[/tex] inches
[tex]$h_f = 2.2 - 0.56$[/tex]
= 1.64 inches
Roll strip contact length (L) = [tex]$\sqrt{R(h_0-h_f)}$[/tex]
[tex]$=\sqrt{14 \times 0.56}$[/tex]
= 2.8 inches
Absolute value of true strain, [tex]$\epsilon_T$[/tex]
[tex]$\epsilon_T=\ln \left(\frac{2.2}{1.64}\right) = 0.2937$[/tex]
Average true stress, [tex]$\overline{\gamma}=\frac{K\sum_f}{1+n}= 31305.56$[/tex] Psi
Roll force, [tex]$L \times b \times \overline{\gamma} = 2.8 \times 9 \times 31305.56$[/tex]
= 788,900 lb
For SI units,
Power = [tex]$\frac{2 \pi FLN}{60}$[/tex]
[tex]$=\frac{2 \pi 788900\times 2.8\times 150}{60\times 44.25\times 12}$[/tex]
= 10399.81168 W
Horse power = 13.9357
A small hot surface at temperature Ti-430K having an emissivity 0.8 dissipates heat by radiation into a surrounding area at T2-400K. If this radiation transfer process is characterized by a radiation heat transfer coefficient h, calculate the value of h (a) 14.4 W/m2.C (b) 114.4 W/m2C (c) 314.4 W/m2.C ( 514.4 W/m2.c
Answer:
389.6 W/m²
Explanation:
The power radiated to the surroundings by the small hot surface, P = σεA(T₁⁴ - T₂⁴) where σ = Stefan-Boltzmann constant = 5.67 × 10⁻⁸ W/m²-K⁴, ε = emissivity = 0.8. T₁ = temperature of small hot surface = 430 K and T₂ = temperature of surroundings = 400 K
So, P = σεA(T₁⁴ - T₂⁴)
h = P/A = σε(T₁⁴ - T₂⁴)
Substituting the values of the variables into the equation, we have
h = 5.67 × 10⁻⁸ W/m²-K⁴ × 0.8 ((430 K )⁴ - (400 K)⁴)
h = 5.67 × 10⁻⁸ W/m²-K⁴ × 0.8 (34188010000 K⁴ - 25600000000 K⁴)
h = 5.67 × 10⁻⁸ W/m²-K⁴ × 0.8 × 8588010000K⁴
h = 38955213360 × 10⁻⁸ W/m²
h = 389.55213360 W/m²
h ≅ 389.6 W/m²
Pie charts should have no more than eight segments. True or False?
Answer:
Explanation:
Pie charts generally should have no more than eight segments.
A large tank, at 500 K and 200 kPa, supplies isentropic air flow to a nozzle. At section 1, the pressure is only 120 kPa. What is the temperature at section 1
A clay sample was consolidated in a triaxial test under an all-around conning pressure of 15 lb/in.2. The sample was then loaded to failure in undrained condition by applying an additional axial stress of 22 lb/in.2. A pore water pressure sensor recorded an excess pore pressure of (Dud)f 5 29 lb/in.2 at failure. Determine the undrained and drained friction angles for the soil
Answer:
- the undrained friction angles for the soil is 25.02°
- the drained friction angles for the soil is 18.3°
Explanation:
Given the data in the question;
First we determine the major principle stress using the express;
σ₁ = σ₃ + (Δσ[tex]_d[/tex] )[tex]_f[/tex]
where σ₃ is the total minor principle stress at failure ( 15 lb/in² )
(Δσ[tex]_d[/tex] )[tex]_f[/tex] is the deviator stress ( -9 lb/in² )
so
σ₁ = 15 lb/in² + 22 lb/in²
σ₁ = 37 lb/in²
Now, we calculate the consolidated-undrained friction angle as follows;
∅ = sin⁻¹[ (σ₁ - σ₃ ) / ( σ₁ + σ₃ ) ]
∅ = sin⁻¹[ (37 - 15 ) / ( 37 + 15 ) ]
∅ = sin⁻¹[ 22 / 52 ]
∅ = sin⁻¹[ 0.423 ]
∅ = 25.02°
Therefore, the undrained friction angles for the soil is 25.02°
- The drained friction angles for the soil;
∅ = sin⁻¹[ (σ₁ - σ₃ ) / ( σ₁ + σ₃ - 2(Δσ[tex]_d[/tex] )[tex]_f[/tex] ) ]
so we substitute
∅ = sin⁻¹[ (37 - 15 ) / ( 37 + 15 - 2( -9 ) ]
∅ = sin⁻¹[ 22 / ( 37 + 15 + 18 ) ]
∅ = sin⁻¹[ 22 / 70 ]
∅ = sin⁻¹[ 0.314 ]
∅ = 18.3°
Therefore, drained friction angles for the soil is 18.3°
HELP! It’s for an architecture class on PLATO
Select the correct answer.
Which association maintains the International Building Code?
A. NFPA
B. ICC
C. EPA
D. DOJ
Answer:
ICC
Explanation:
The International Building Code (IBC) is a model building code developed by the International Code Council (ICC). It has been adopted for use as a base code standard by most jurisdictions in the United States.
You will only have two attempts to answer this question correctly. Assuming you determine the required section modulus of a wide flange beam is 200 in3, determine the lightest beam possible that will satisfy this condition.
Answer:
W18 * 106
Explanation:
Section modulus of wide flange = 200 m^3
Determine the value of the lightest beam possible
The lightest beam possible that will satisfy the given condition will have a section modulus ≥ 200m^3 ( note: it will also be the nearest to 200 in^3 )
From Beam Table ; The Lightest beam with its section modulus( 204 in^3) > 200in^3 is W18 * 106