Answer:
While calculating the stresses in a body since we we assume a constant distribution of stress across a cross section if the body is loaded along the centroid of the cross section , this assumption of uniformity is assumed only on the basis of Saint Venant's Principle.
Saint venant principle states that the non uniformity in the stress at the point of application of load is only significant at small distances below the load and depths greater than the width of the loaded material this non uniformity is negligible and hence a uniform stress distribution is a reasonable and correct assumption while solving the body for stresses thus greatly simplifying the analysis.
Answer:
The resultant moment is 477.84 N·m
Explanation:
We note that the resultant moment is given by the moment about a given point
The length of the sides of the formed triangles are;
l = sin(40°) × 4/sin(110°) ≈ 2.736
Taking the moment about the lower left hand corner of the figure, with the convention that clockwise moments are positive, we have;
The resultant moment, ∑m, is given as follow;
∑M = 250 N × 4 m + 400 N × cos(40°) × 4 m - 400 N × cos(40°) × 2 m + 400 N × sin(40°) × 2 m × tan(40°) - 600 N × cos(40°) × 2 m - 600 N× sin(40°) × 2 m × tan(40°) = 477.837084 N·m
Therefore, the resultant moment, ∑m ≈ 477.84 N·m clockwise.
Answer:
a) heat gain per unit tube length = 
b) heat gain per unit tube length = 
Explanation:
Assumptions:
- Constant properties
- Steady state conditions
- Negligible effect of radiation
- Negligible constant resistance between tube and insulation
- one dimensional radial conduction
a) What is the heat gain per unit tube length

Therefore 








heat gain per unit tube length = 
b) What is the heat gain per unit length if a 10-mm-thick layer of calcium silicate insulation (k_ins = 0.050 W/m.K) is applied to the tube

and
are the same, but
changes.
Therefore:


The total resistance 
heat gain per unit tube length = 
Answer:


Explanation:
Given that:
x(t) = 10 sin(10t) . sin (15t)
the objective is to find the power and the rms value of the following signal square.
Recall that:
sin (A + B) + sin(A - B) = 2 sin A.cos B
x(t) = 10 sin(15t) . cos (10t)
x(t) = 5(2 sin (15t). cos (10t))
x(t) = 5 × ( sin (15t + 10t) + sin (15t-10t)
x(t) = 5sin(25 t) + 5 sin (5t)
From the knowledge of sinusoidial signal Asin (ωt), Power can be expressed as:

For the number of sinosoidial signals;
Power can be expressed as:

As such,
For x(t), Power 



For the number of sinosoidial signals;

For x(t), the RMS value is as follows:





C, I took the test already.