Answer:
(a) T = W/2(1-tanθ) (b) 39.81°
Explanation:
(a) The equation for tension (T) can be derived by considering the summation of moment in the clockwise direction. Thus:
Summation of moment in clockwise direction is equivalent to zero. Therefore,
T*l*(sinθ) + W*(l/2)*cosθ - T*l*cosθ = 0
T*l*(cosθ - sinθ) = W*(l/2)*cosθ
T = W*cosθ/2(cosθ - sinθ)
Dividing both the numerator and denominator by cosθ, we have:
T = [W*cosθ/cosθ]/2[(cosθ - sinθ)/cosθ] = W/2(1-tanθ)
(b) If T = 3W, then:
3W = W/2(1-tanθ),
Further simplification and rearrangement lead to:
1 - tanθ = 1/6
tanθ = 1 - (1/6) = 5/6
θ = tan^(-1) 5/6 = 39.81°
Answer:
That's either a cable-stayed bridge or a cantilever bridge
Answer:
2.7 W/m^2K
Explanation:
Area of pane = 5 m x 6 m = 30 m^2
Solar irradiation Gs = 900 W/m2
Heat rate on panel = Gs x area = 900 x 30 = 27000 W
absorptivity to solar irradiation αs = 0.92
Therefore, absorbed heat is
0.92 x 27000 = 24840 W
For heat gain,
From E = §AT^4
Where § = stefan's constant = 5.7x10^-8 Wm^-2K^-1
T = temperature of panel
24840 = 5.7x10^-8 x 30 x T^4
24840 = 1.71x10^-6 x T^4
1.453x10^10 = T^4
T = 347.167 K
For net heat gain,
From E = §A(T^4 - T^4sur)
24840 = 5.7x10^-8 x 30 x (T^4 - T^4sur)
24840 = 1.71x10^-6 x (1.453x10^10 - T^4sur)
24840 = 24846.3 - 1.71x10^-6(T^4sur)
-6.3 = -1.71x10^-6(T^4sur)
3684210.526 = T^4sur
Tsur = 43.81 K
Also for convective heat,
E = Ah(T - Tsur)
24840 = 30h(347.167 - 43.81)
24840 = 30h x 303.357
81 = 30h
h = 2.7 W/m^2K
Answer:
Glulam is an industrial wood product that optimizes the structural qualities of wood. These structural elements are composed of individual segments whose dimensions correspond to the natural wood from which they originate. These segments are joined at their ends for the production of longer elements, which are then glued with adhesives in order to create the required dimensions of the structural elements.
Explanation:
Thanks to its composition, larger glulam elements can be manufactured from smaller trees. Glulam offers builders and designers the strength and versatility of the structural elements of wood, but they would no longer depend on wood that comes from old trees.
Glulam has a higher stiffness than ordinary wood and is stronger than steel. This means that the structural elements of glulam have greater flexibility and can be used in the construction of homes or bridges.
