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Old 06-30-2013, 10:10 PM
bobbychinn bobbychinn is offline
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Quote:
Originally Posted by lawrencee View Post
1.What is the correct included grinding angle for a jobber's steel drill bit?
A.109
B.112
C.118
D.121

2.Which colour of tungsten electrode is used to weld aluminium?
A.Red.
B.Green.
C.Yellow.
D.Blue.

3.What is used to prepare a joint on cold rolled iron for brazing?
A.Acid.
B.Degreaser.
C.Grinding disk.
D.Wire brush.

4.How should a 15-m wire rope be stored?
A.Coiled dry and hung on a hook in a dry area.
B.Wound dry on a reel and stored in a dry area.
C.Lubricated, coiled, and hung on a hook.
D.Lubricated and wound on a reel.

5.What is the minimum requirement to layout a pattern for a square-to-round on centre?
A.3/4 of the plan view.
B.1/4 of the plan view.
C.1/2 of the plan view.
D.Full plan view.

6.What is the net blank cut size for a 90 14-in. diameter seven-piece elbow, used in a material handling system?

A.33.18 in. 44 in.
B.44.24 in. 44 in.
C.55.29 in. 44 in.
D.64.50 in. 44 in.

7.If 24 gauge metal is 0.686 mm (0.027 in.) thick, approximately how much must be taken from the circumference of a round pipe to make a small end?
A.3/32 in.
B.1/8 in.
C.3/16 in.
D.7/32 in.

8.A top takeoff used in a residential heating system has an equivalent length of 40 ft. with a design static pressure loss of 0.08 in./wg. What is the resulting friction loss?
A.0.032 in./wg
B.0.32 in./wg
C.3.2 in./wg
D.32 in./wg

9.Which combination of materials will corrode the quickest due to electrolysis (or galvanic reaction)?
A.Aluminium and copper.
B.Steel and copper.
C.Nickel and copper.
D.Lead and copper.

10.To allow proper air movement, what diameter of round pipe is required for a kitchen exhaust fan to move 2 000 cfm at 1 500 fpm?
A.6 in.
B.8 in.
C.12 in.
D.16 in.

11.What is the maximum allowable leakage for a 12-in. diameter duct, 250 ft. long with a leakage allowance of 6 cfm per 100 sq. ft. in surface area?

A.11.78 cfm
B.47.12 cfm
C.49.78 cfm
D.53.12 cfm

12.How much material would be required to cover a 12-in. round five-piece 90 elbow with a full throat and covered with 2 in. insulation and a 3/4 in. lap on the circumference of each gore?
A.28 5/8 in. 51 in.
B.33 3/8 in. 44 3/4 in.
C.35 3/16 in. 44 3/4 in.
D.38 3/16 in. 51 in.

13.What is the unit cooling capacity of a 3 100 cfm roof top unit with an economizer and an enthalpy difference of 6.5 Btu/lb. between the mixture air and the supply air?
A.1.80 tons
B.2.50 tons
C.6.75 tons
D.7.50 tons

14.A register is to deliver 500 cfm at a velocity pressure of 0.0126 in./wg and an AK factor of 70%. What is the register area?
A.123.32 sq. in.
B.176.17 sq. in.
C.182.89 sq. in.
D.228.80 sq. in.

15.A fan is designed to deliver 10 500 cfm (4 955 l/s) through a terminal reheat system when turning at 1 253 rpm. What corrective action should be taken if the measured fan performance is 9 960 cfm (4 700 l/s) when turning at 1 253 rpm?
A.Decrease the motor pulley size.
B.Increase the fan pulley size.
C.Tighten the fan belts.
D.Increase the motor pulley size.

16.How much material is required to fabricate an open chute 30 in. wide, with sides 12 in. high, to convey dust a vertical distance of 6 ft. and a horizontal distance of 10 ft. 4 3/4 in.?
A.30 sq. ft.
B.54 sq. ft.
C.74 sq. ft.
D.84 sq. ft.

17.What is the resulting mixture temperature if an economizer is allowing 2 000 cfm of 35F air to mix with the return air 8 000 cfm and 75F?
A.45F
B.50F
C.60F
D.65F

18.Air at 25C (77F) is capable of holding 144 grains of moisture, but is only holding 92. What is the current relative humidity?
A.32%
B.41%
C.64%
D.80%

19.What is the minimum number of support hangers required for installing roof gutters on a roof that measures 100 ft. in length?
A.23
B.26
C.30
D.34

20.What is the amount of fall when installing 45 ft. of gutter with a ratio of 1/8 in. per 10 ft.?
A.1/8 in.
B.3/8 in.
C.1/2 in.
D.9/16 in.



1.C
2.B
3.B
4.D
5.B
6.C
7.C
8.A
9.A
10.D
11.B
12.A
13.D
14.D
15.D
16.B
17.D
18.C
19.D
20.D
Hi
I do not understand question 6,8,11,12,13,14 can someone briefly explain how they got the answer or just the formulas used please. Thanks
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