Civil and Environmental Engineering Answers

a 30m weighing 0.900kg has a cross-sectional area 0.0485cm^2. the tape measures 30.000m when supported throughout under a tension of 5kg. the modulus of elasticity is 2.1x10^6kg/cm. what tension is required to make the tape measure 30m when supposed only at the two ends?

Calculate the size of a rectangular sedimentation tanks to treat a flow of 12,000 m3/d. Adopt an overflow rate of 20 m3/m2-d and detention time of 4 hours. Use two units in parallel. What will be the minimum weir length required if the weir overflow rate is not to exceed 300 m3/m-d? Also check the horizontal velocity.

Calculate the size of a rectangular sedimentation tanks to treat a flow of 12,000 m3/d. Adopt an overflow rate of 20 m3/m2-d and detention time of 4 hours. Use two units in parallel. What will be the minimum weir length required if the weir overflow rate is not to exceed 300 m3/m-d? Also check the horizontal velocity.

What are the METHODS OF FORECATING POPULATION?

A traffic light and signal pole is subjected to the weight of each the weight of traffic signal W_s = 45 lb and the weight of the road lamp W_L = 55 lb. The pole is fixed at the base. Find the principal normal stresses and the maximum shear stress on element B located 19 ft above the base (see figure). Assume that the weight of the pole and later arms is included in the signal and lamp weights. [Ans. sigma_max = 2689 psi]

Determine the horizontal and vertical components of reaction on the member at the pin A, and the normal reaction at the roller B.

determine the force P required to maintain the 200 kg engine in the position for which theta = 30 degree. The diameter of the pulley at B is negligible.

A 24.72 meter distance will be laid out using a 50 m tape that is .12 m too long. Where on the tape would you put the mark in order to layout the required 24.72 meter?