Civil Engineering - Applied Mechanics

Exercise :: Applied Mechanics - Section 5
36.
Pick up the incorrect statement from the following. In a simple harmonic motion

A.
velocity is maximum at its mean position B.
velocity is minimum at the end of the storke C.
acceleration is minimum at the end of the stroke D.
acceleration is zero at the mean position.

Answer: Option C

Explanation:

37.
The gravitational force makes a satellite go round the earth in a circular orbit, if it is projected with an initial velocity of

A.
8.04 km/sec at a height of 285 km B.
11.11 km/sec at a height of 37, 400 km C.
11.26 km/sec, the satellite escapes the pull of the earth D.
all the above.

Answer: Option D

Explanation:

38.
The point about which combined motion of rotation and translation of a rigid body takes place, is known as

A.
Virtual centre B.
Instantaneous centre C.
Instantaneous axis D.
Point of rotation E.
All the above.

Answer: Option B

Explanation:

39.
A particle is dropped from the top of a tower 60 m high and another is projected upwards from the foot of the tower to meet the first particle at a height of 15.9 m. The velocity of projection of the second particle is

A.
16 m/sec B.
18 m/sec C.
20 m/sec D.
22 m/sec.

Answer: Option C

Explanation:

40.
A point subjected to a number of forces will be in equilibrium, if

A.
sum of resolved parts in any two directions at right angles, are both zero B.
algebraic sum of the forces is zero C.
two resolved parts in any two directions at right angles are equal D.
algebraic sum of the moments of the forces about the point is zero E.
none of these.

Answer: Option A

Explanation: