A single thread power screw is 36 mm in diameter with a pitch of
6 mm. A vertical load on the screw imposes a force of 9 kN. The
coefficients of friction are 0.09 for the collar and 0.16 for the
screw. The effective diameter of the collar is 52 mm. Find the
overall efficiency and torque required to raise and lower this
load.
The mean diameter of the square threaded screw having pitch of
10 mm is 50 mm. A load of 20 kN is lifted through a distance of 170
mm. Find the work done in lifting the load and the efficiency of
the screw, when
1. The load rotates with the screw, and
2. The load rests on the loose head which does not rotate with the
screw.
The external and internal diameter of the bearing surface of the
loose head...
Measurements of a number of fittings show that the pitch diameter of the thread is normally distributed with a mean of 8.007 mm and a standard deviation of 0.005 mm. The design specifications require that the pitch diameter be 8 ± 0.01 mm. Estimate the percentage of fittings that will be within tolerance.
A regulation tennis ball has a diameter of 2½ inches; a
Ping-Pong ball has a diameter of 1½ inches.
a. Find and compare the volumes of the two types of balls.
b. Find and compare the surface areas of the two types of
balls.
Please show steps
An inspector has the job of checking a screw-making machine at
the start of each day. She finds that the machine needs repairs
pairs one day out of ten. When the machine does need repairs, all
the screws it makes are defective. Even when the machine is working
properly, 5% of the screws it makes are defective; these defective
screws are randomly scattered through the day's output. Use a
calculator to get approximate answers to the following lowing
questions. What...
A soil sample weighing 122g has diameter and length equal to 4.5
inches
and 11 inches, respectively. The moisture content in soil came out
to be 40 %. If specific gravity of soil
solids is 2.67. Find Bulk unit weight, dry mass of sample, voids
ratio, porosity, dry unit weight and degree
of saturation of soil sample.
The existing record shows machine bearing has a mean diameter of
0.6 inches. Bearing diameter is known to be normally distributed
with standard deviation σ = 0.1 inches. (Additional note: If the
mean diameter of bearings is larger or smaller than 0.6 inches,
then the process is out of control and must be adjusted.) A random
sample of 60 bearings are selected, and the average diameter of the
bearing from this sample is 0.55 inches. Use α=0.02 to test the...
2. A golf association requires that golf balls have a diameter
that is 1.68 inches. To determine if golf balls conform to
thestandard, a random sample of golf balls was selected. Their
diameters are shown in the accompanying data table. Do the golf
balls conform to the standards? Use the a= 0.05 level of
significance.
Golf Ball Diameter
1.682 1.676 1.681
1.684 1.679 1.686
1.684 1.685 1.673
1.685 1.682 1.675
a. First determine the appropriate hypotheses.
H0: (p,o,u) (>,<,=,≠) BLANK...
A camera lens has a power of +1.75D. If the diameter of the lens
is 5.7 cm, what is the f-stop of the lens?
Does a single-lens camera produce a real or virtual image?
Explain?
A farsighted person has a near point of 38 cm. She holds her
book at 25 cm to read, what is the focal length and power of the
lens necessary for her to read?
An electron travels at a velocity of 7.5x10^6 m/s through a...
We have an HID light fixture that has a luminous diameter of 18
inches. What is the number of footcandles found at a point that is
4.5 feet over from the center of the fixture and 12 feet down? The
candlepower distribution curve for this fixture is as below in
Table 1:
? - I
0 - 8564
5 - 8817
15 - 10964
25 - 12534
35 - 11845
45 - 9025
Table 1