Engineering Answers

3-1. A vector Bb is 1 in. long and has a direction-sense of 45°. Vector Cc

is 1½ in. long and has a direction-sense of 150°. Find their vector sum.

put together a document (500 words) in which you evaluate your chosen design solution to the requirements of the customer and the PDS

The city of a population of 161,565 has requested to evaluate its solids waste collection system.

Determine:

i) mean time per collection stop plus the mean time to reach the next stop,

ii) number of pickup locations per load

iii) minimum number of trucks the city must own.

Consider the following data:

a) Average truck capacity =18 m3

b) Average observed compaction ratio =3.28

c) Crew size = 2 persons

d) Number of pickups = 1/week (no rear-of-house service)

e) Average number of residence per stop= 2.5

f) Average uncompact density = 122 kg/m3

g) Average transport time to disposal site including delay and dumping = 1.5 h/trip

h) Average number of trips to disposal site =2/day

i) Rest breaks = 2 at 15 min

j) Average maintenance downtime = 36 min/day

k) Average work day = 8 hours

l) Average percentage of truck out of service for majority repairs = 15%

m) Average number of cans per stop = 2.5/wk at 0.0911 m3/can

A contractor is trying to estimate the distance to be expected of drawdown of 4.81 m from pumping well under the following conditions:

a) Pumping rate 0.028 m3/s

b) Pumping time = 1066 days

c) Drawdown in observation well = 9.52 m

d) Observation well is located 10.0 m from the pumping well

e) Aquifer material = medium sand

f) Aquifer thickness = 14.05 m

Assume that the well is fully penetrating in an unconfined aquifer.

5. Two shafts 30 in. apart, each carrying a four-step pulley, are to be connected by a cross belt. The driving shaft is to turn 180 rpm while the driven shaft is to turn 50, 150, 250, and 600 rpm. The smallest step of the driver is 10 in. in diameter. Find (a) the diameters of all the steps, (b) angle of contact for each pair of pulleys, and (c) belt length. PLEASE EXPLAIN THE DEATILED ANSWER WITH SOLUTION.