# Engineering Mechanics

(Joyce) #1

Chapter 6 : Centre of Gravity  99

1. How many centres of gravity a body has?

2. Describe the various methods of finding out the centre of gravity of a body.

3. How would you find out the centre of gravity of a section, with a cut out hole?

OBJECTIVE TYPE QUESTIONS

1. The centre of gravity of an equilateral triangle with each side (a) is ...... from any of the
three sides.

``(a)``

``````3
2``````

``````a
(b)``````

``````2
3``````

``````a
(c)
23``````

``````a
(d)
32``````

``a``

1. The centre of gravity of hemisphere lies at a distance of ......form its base measured along

``(a)``

``````3
8``````

``````r
(b)``````

``````3
8 r (c)``````

``````8
3``````

``````r
(d)``````

``````8
3 r``````

1. The centre of gravity of a right circular cone of diameter (d) and height (h) lies at a
distance of ...... from the base measured along the vertical radius.

``````(a)
2``````

``````h
(b)
3``````

``````h
(c)
4``````

``````h
(d)
6``````

``h``

1. A circular hole of radius (r) is cut out from a circular disc of radius (2r) in such a way that the
diagonal of the hole is the radius of the disc. The centre of gravity of the section lies at
(a) Centre of a disc (b) Centre of the hole
(c) Somewhere in the disc (d) Somewhere in the hole