Civil and Environmental Engineering Answers

Predict the mode of decay of (a) plutonium-239, (b) Indium-120. Show your solution

Predict the mode of decay of (a) plutonium-239, (b) Indium-120. Show your solution

Which element undergoes alpha decay to form lead- 208? Show your solution

two c310 x 45 channels are latticed together so they have equal moments of inertia about the principal aves. determine the minimm length of a column having this section. assuming pinned ends. e 200 gpa. and a proportional limit of 240 mpa. what safe load will the column carry for a length of 12 m with a factor of safety of 2.5?

A city discharges 100 (cum. Sec) m3/sec of sewage into a river, which is fully saturated with oxygen and flowing at the rate of 150 m3/sec during its lean days with a velocity of 0.1 m/sec. The 5th day BOD of sewage at the given temperature is 280 mg/L. Find when and where the critical DO deficit will occur in the downstream portion of the river and what is its amount. Assume f = 4.0 (Self-purification constant and KD = 0.1. *

A solid shaft 100 mm in diameter is subjected simultaneously to an axial compressive force of 50 kN and to a torque that twist through an angle of 1.5

A flat bar 75 mm wide by 9 mm thick and 1.2 m long is subjected to end moments of 202.5 N.m. Compute the deflection of the beam at the midspan if E = 200 000 MPa.

What is the ratio of the shear modulus G to the modulus of elasticity of steel if it has a Poisson’s ratio of 0.25.

A wooden log is to be used as a foot bridge to span a gap. The log is required to support a concentrated load of 30 kN at midspan. Allowable shearing stress is 0.70 Mpa. Determine the diameter of the log that would be needed.