Answer:
2A : 2.94 inches
2B : 2.718 in²
Step-by-step explanation:
We are given the formula
Highest Ultimate load = max compressive strength x cross sectional area
I think there is a typo in the equations here because the above equation was repeated twice, i'm guessing the second equation should be:
Highest Ultimate load = max tensile strength x cross sectional area
Problem 2A:
Given:
Highest Ultimate load = 135,900 lb
max compressive strength (concrete) = 5,000 lbs/in²
cross sectional area = π r² ; where r is the radius of the circle in inches
simply substitute the above into the first formula and solve for r:
Highest Ultimate load = max compressive strength x cross sectional area
135,900 = 5,000 x π r²
π r² = 135900 / 5000
π r² = 27.18
r² = 27.18 / π
r = √ ( 27.18 / 3.14 )
r = 2.94 inches
Problem 2B:
Given:
Highest Ultimate load = 135,900 lb
max tensile strength (steel) = 50,000 lbs/in²
cross sectional area in inches² = (we are asked to find this)
Again simply substitute the above into the 2nd equation at the top:
Highest Ultimate load = max tensile strength x cross sectional area
135,900 = 50,000 x cross sectional area
cross sectional area = 135,900 / 50,000
cross sectional area = 2.718 in²
