Civil Engineering - Applied Mechanics

46.
Pick up the incorrect statement from the following :
The C.G. of a circle is at its centre
The C.G. of a triangle is at the intersecton of its medians
The C.G. of a rectangle is at the intersection of its diagonals
The C.G. of a semicircle is at a distance of r/2 from the centre
The C.G. of an ecllipse is at the intersection of axes.
Answer: Option
Explanation:
No answer description is available. Let's discuss.

47.
A 49 kg lady stands on a spring scale in an elevator. During the first 5 sec, starting from rest, the scale reads 69 kg. The velocity of the elevator will be
10 m/sec
15 m/sec
20 m/sec
25 m/sec.
Answer: Option
Explanation:
No answer description is available. Let's discuss.

48.
Pick up the correct statement from the following. A rubber ball when strikes a wall rebounds but a lead ball of same mass and velocity when strikes the same wall, falls down
rubber and lead balls undergo equal changes in momentum
change in momentum suffered by lead ball is less that of rubber ball
momentum of rubber ball is less than that of lead ball
none of these.
Answer: Option
Explanation:
No answer description is available. Let's discuss.

49.
The instantaneous centre of a member lies at the point of intersection of two lines drawn at the ends of the member such that the lines are inclined to the direction of motion of the ends at
30°
45°
60°
90°
Answer: Option
Explanation:
No answer description is available. Let's discuss.

50.
A rod 5 m in length is moving in a vertical plane. When it is inclined at 60° to horizontal, its lower end is moving horizontally at 3 m/sec and upper end is moving in vertical direction. The velocity of its upper end, is
0.5 m/sec
1.0 m/sec
1.5 m/sec
2.5 m/sec
3.0 m/sec
Answer: Option
Explanation:
No answer description is available. Let's discuss.