# MCQs on Terminology of Spur Gears

1 - Question

In cycloidal gears contact area is

a) Comparatively smaller
b) Comparatively larger
c) Can’t be determined
d) None of the listed

Explanation: Convex flank on one tooth meets with concave on the other thus increasing the contact area.

2 - Question

Involute gears have greater contact area as compared to cycloidal gears.

a) True
b) False

Explanation: There is mating of two convex surfaces and hence lesser contact area.

3 - Question

Cycloidal teeth consist of

a) Hypocycloid curve
b) Epicycloid gear
c) Both hypocycloid curve and epicycloid curve
d) None of the mentioned

Explanation: It consist of both and thus are hard to manufacture.

4 - Question

Pressure angle remains constant in case of involute profile.

a) True
b) False

Explanation: The common normal always passes through the pitch point and thus maintain the constant inclination.

5 - Question

Pressure angle is _____ in case of cycloidal teeth.

a) Constant
b) Variable
c) zero
d) None of the listed

Explanation: Cycloidal teeth consist of two profiles.

6 - Question

Velocity ratio is the ratio angular velocity of driving gear to that of driven gear.

a) True
b) False

Explanation: Velocity ratio is simply the angular velocities ratio

7 - Question

Velocity ratio and transmission ratio are the same thing.

a) True
b) False

Explanation: Transmission ratio is measured between first and last gear.

8 - Question

Contact ratio is always

a) =1
b) >1
c) <1
d) Can’t be determined

Explanation: Some overlapping is essential for continuous transfer of power.

9 - Question

Product of diametric pitch and circular pitch is?

a) π
b) 1/π
c) None of the listed
d) 2

Explanation: CP=πd/z and circular pitch=z/d.

10 - Question

Diameteral pitch is 5, then calculate module of the gear.

a) 0.2
b) 0.4
c) 5
d) 10