Civil Engineering - Applied Mechanics

Exercise :: Applied Mechanics - Section 5
1.
The centre of gravity of a homogenous body is the point at which the whole

A.
volume of the body is assumed to be concentrated B.
area of the surface of the body is assumed to be concentrated C.
weight of the body is assumed to be concentrated D.
all the above.

Answer: Option C

Explanation:

2.
Pick up the correct statement from the following :

A.
If two equal and perfectly elastic smooth spheres impinge directly, they interchange their velocities. B.
If a sphere impinges directly on an equal sphere which is at rest, then a fraction (1 - e ^{2} ) the original kinetic energy is lost by the impact. C.
If a smooth sphere impinges on another sphere, which is at rest, the latter will move along the line of centres. D.
If two equal spheres which are perfectly elastic impinge at right angles, their direction after impact will still be at right angles. E.
All the above.

Answer: Option E

Explanation:

3.
Centre of gravity of a thin hollow cone lies on the axis of symmmetry at a height of

A.
one-half of the total height above base B.
one-third of the total height above base C.
one-fourth of the total height above base D.
none of these.

Answer: Option B

Explanation:

4.
A ball of mass 1 kg moving with a velocity of 2 m/sec collides a stationary ball of mass 2 kg and comes to rest after impact. The velocity of the second ball after impact will be

A.
zero B.
0.5 m/sec C.
1.0 m/sec D.
2.0 m/sec.

Answer: Option C

Explanation:

5.
Periodic time of a particle moving with simple harmonic motion is the time taken by the particle for

A.
half oscillation B.
quarter oscillation C.
complete oscillation D.
none of these.

Answer: Option C

Explanation: