Mechanical Engineering Review Online

A pair of meshing spur gear has a module of 3. The pinion has 20 teeth and the gear has 30 teeth. Find the

1. Pitch diameter of each gear

a. 60 mm and 90 mm

b. 30 mm and 60 mm

c. 50 mm and 80 mm

d. 40 mm and 70 mm

2. Center distance between gears

a. 68 mm

b. 79 mm

c. 82 mm

d. 75 mm

3. A 220 mm diameter of 14.5 degrees involute gear is used to transmit 50 kW at 580 rpm. Find the total force transmitted on the gear.

a. 7.48 kN

b. 8.32 kN

c. 6.55 kN

d. 9.77 kN

4. A 12-in diameter gear diameter gear is used to transmit 30 kW at 850 rpm. Find the tangential force acting on each gear.

a. 4.35 kN

b. 3.32 kN

c. 5.22 kN

d. 2.21 kN

5. An internally meshing gear has a center distance of 25-in. If the larger gear has a diameter of 55-in, find the diameter of the internal gear.

a. 6 in

b. 5 in

c. 4 in

d. 3 in

6. A gear has a pitch diameter of 10-in and diameteral pitch of 6, calculate the outside diameter.

a. 11.75 in

b. 12.50 in

c. 10.75 in

d. 9.50 in

7. A 14.5 deg full-depth gear has a tooth thickness of 0.30-in, find the addendum distance.

a. 1.0870 in

b. 0.1910 in

c. 0.8871 in

d. 0.5531 in

8. A 20 deg full-depth gear has tooth thickness of 0.20-in, find the addendum distance.

a. 0.8812 in

b. 0.7671 in

c. 0.1273 in

d. 0.6281 in

9. What is the equivalent diametral pitch of a gear that has a module of 3?

a. 8.47 in

b. 7.35 in

c. 9.33 in

d. 5.32 in

10. A standard 20 deg full-depth spur gear has 26 teeth and circular pitch of 0.785-in. Compute the working depth.

a. 0.6872 in

b. 0.9972 in

c. 0.7581 in

d. 0.5393 in

11. How many revolutions per minute is a spur gear turning if it has a module of 3 mm, 42 teeth, and pitch line velocity of 2600 mm/sec?

a. 394.10 rpm

b. 355.81 rpm

c. 331.81 rpm

d. 300.0 rpm

12. How many revolutions per minute is a spur gear turning, if it has 30 teeth, a circular pitch of 0.785-in and a pitch line velocity of 15 ft/sec?

a. 351.28 rpm

b. 551.28 rpm

c. 458.60 rpm

d. 228.21 rpm

13. What is the pitch diameter of a 42 teeth spur gear having a circular pitch of 1.60?

a. 28.28 in

b. 32.28 in

c. 21.39 in

d. 20.71 in

14. A spur gear 20 deg full-depth involute teeth has an outside diameter of 190 mm and module of 5.2778. Find the number of teeth.

a. 30

b. 32

c. 34

d. 36

15. A pair of meshing gears has a diametral pitch of 10.7140, a center distance of 2.8-in, and a velocity ratio of 2. Find the number of teeth of the smaller gear.

a. 26

b. 20

c. 36

d. 40

16. A 14.5 degrees full-depth involute gear has an outside diameter of 5-1/3 in and diametral pitch of 6. Find the number of teeth.

a. 30

b. 34

c. 38

d. 40

17. Two parallel shafts have a center distance of 16-in. One of the shafts carries a 42-tooth, 2 diametral pitch gear which drives a gear on the other shaft at a speed of 160 rpm. How fast is the 42-tooth gear turning?

a. 75.22 rpm

b. 83.81 rpm

c. 62.21 rpm

d. 58.21 rpm

18. Two parallel shafts have an angular velocity ratio of 4 to 1 are connected by gears, the largest of which has 40 teeth. Find the number of teeth of smaller gear.

a. 14

b. 12

c. 10

d. 16

19. Determine the pitch diameter of a gear with 30 teeth, 5 diametral pitch.

a. 15

b. 18

c. 20

d. 12

20. Find the distance between centers of a pair of gears, one of which has 14 teeth and the other 38 teeth. The diametral pitch is 8.

a. 3.25 in

b. 4.55 in

c. 5.38 in

d. 7.88 in

21. Find the circular pitch of gear having a center distance of 12 in and has 24 teeth pinion with 56 teeth gear.

a. 0.9425 in

b. 0.5153 in

c. 0.3277 in

d. 0.2011 in

A machinist made two 9 diametral pitch spur gears to be mounted at a center distance of 18 inches with a speed ratio of 8 to 10. Compute the following:

22. Pitch diameter of each gear

a. 16 and 20 in

b. 18 and 22 in

c. 20 and 24 in

d. 22 and 26 in

23. Number of teeth of each gear

a. 144 and 180

b. 166 and 196

c. 100 and 120

d. 182 and 220

24. Outside diameter of each gear

a. 16.22 and 20.22 in

b. 18.22 and 22.22 in

c. 32.22 and 38.22 in

d. 14.22 and 18.22 in

25. Circular pitch

a. 0.5521 in

b. 0.6871 in

c. 0.3491 in

d. 0.7100 in

26. Shaft A with 12-in pulley diameter running at 280 rpm is connected to shaft B by means of 30-in diameter pulley. Another pulley on shaft B, 15-in diameter is connected to 11-in diameter pulley on shaft C. Determine the speed of shaft C.

a. 145.2 rpm

b. 152.7 rpm

c. 168.2 rpm

d. 177.8 rpm

27. A pulley has tangential velocity of 80 fpm. If pulley diameter is 12-in, determine the speed of the pulley.

a. 20.21 rpm

b. 28.32 rpm

c. 25.46 rpm

d. 30.28 rpm

28. Four cylinders rolling in opposite directions has a speed ratio of A:B:C:D = 6:4:2:5. If the center distance between cylinder A and C is 75-in, determine the diameter of cylinder D.

a. 20.1 in

b. 28.8 in

c. 23.2 in

d. 25.7 in

29. Two cylinders rolling in the same direction has a speed ratio of 2.8 and center distance of 60 cm. Determine the diameter of the larger cylinder.

a. 78.9 in

b. 68.7 in

c. 55.9 in

d. 73.5 in

30. Two cylinders rolling in the opposite direction has a speed ratio of 3.5. If the diameter of drive is 12-in, find the center distance between cylinders.

a. 27 in

b. 30 in

c. 25 in

d. 35 in

31. An 820 mm diameter circular saw blade is driven by 1500 rpm motor with gear speed ratio of 1.5. Find the peripheral speed of the blade.

a. 140.83 fps

b. 158.02 fps

c. 168.81 fps

d. 147.28 fps

Answer Key (Handwritten)