71. In spur gear, the circle on which the involute is generated is called

1. base circle
2. addendum circle
3. pitch circle
4. prime circle

72. Which pair of gears usually has higher fricitional losses?

1. Spur gears
2. Helical gears
3. Bevel gears
4. Worm and worm wheel

73. In gears, the most frequently used pressure angle is

1. 10°
2. 17°
3. 11°
4. 22.5°

74. In which type of gears, the efficiency is less but speed reduction ratio is highest

1. Spur gear
2. Helical gear
3. Bevel gear
4. Worm gear

75. A gear having 100 teeth is fixed and another gear having 25 teeth revolves around it, the centre lines of both gears being joined by an arm. How many revolutions will be made gear of 25 teeth for one revolution of arm:

1. 4
2. 3
3. 5
4. 6

76. Herringbone gears are

1. Spiral gears
2. Double helical gears
3. Large worm gears
4. Spur gears with small teeth

77. Which of the following parameters is considered while designing an automotive gearbox?

1. Load profile only
2. Driving style only
3. Road profile only
4. All of the above

78. The radial distance of a tooth from the pitch circle to the bottom of the tooth is called

1. dedendum
2. addendum
3. clearance
4. working depth

79. Which of the following gears is used in the steering wheel of car?

1. Bevel
2. Helical
3. Spur
4. Rack and pinion

80. The difference between space width and tooth thickness is

1. Clearance
2. Backlash
3. Tooth space
4. Flank