MACHINE SHOP CALCULATION - OD1640 - LESSON 2/PE 2
(2) Convert 304.801 millimeters to inches.
e.
If two gears have 180 and 40 teeth respectively, what is the ratio of
the numbers of teeth?
f.
Divide 80 trucks between two sergeants in the ratio of 5 to 3.
g.
The efficiency of a machine is commonly stated as being the ratio of
the output to the input (E = O/I).
E = efficiency, O = output, and I =
output. Suppose the input in a motor is 7000 watts and the output is 6500
watts. What is the efficiency of this motor?
h.
Use the rules of proportion to solve the following problems:
(1) 70 : 45 :: 45 : X
(2) 3 1/4 : 7 4/5 :: 15 : X
(3) X : 5.6 :: 45 : 125
i.
Study the gear train in figure 29 on the following page and find the
rpm of the 36-tooth gear.
j.
A certain single-thread worm makes 25 revolutions-per-second.
It
turns a worm wheel that has 27 teeth. How many revolutions-per-minute will
this worm gear make?
k.
Solve for the following sides of the right triangle:
(1) Find side a if sin A = 0.8, and side c = 18.5 cm.
(2) Find side b if cos A = 0.35 and side c = 4.25 cm.
(3) Find side a if tan A = 1.902 and side b = 3.75 cm.
1.
Use the instructions for calculation of angles in paragraph 4, Lesson
2, Task 3 (on page 56) to solve the following problems:
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