Mechanical Engineering - Theory of machines
Exercise :: Theory of machines - Section 1
21.
When the two elements of a pair have a surface contact when relative motion takes place and the surface of one element slides over the surface of the other, the pair formed is known as a
A.
lower pair B.
higher pair C.
self-closed pair D.
force-closed pair
Answer: Option A
Explanation:
22.
The centre distance between two meshing involute gears is equal to
Answer: Option A
Explanation:
23.
The two elements of a pair are said to form a __________ when they permit relative motion between them.
A.
open pair B.
kinematic pair
Answer: Option B
Explanation:
24.
When the axes of the shafts, over which the gears are mounted, move relative to a fixed axis, then the train is known as reverted gear train.
Answer: Option B
Explanation:
25.
In under damped vibrating system, the amplitude of vibration
A.
decreases linearly with time B.
increases linearly with time C.
decreases exponentially with time D.
increases exponentially with time
Answer: Option C
Explanation: