The unit of rotational inertia of a body in C.G.S system is
cm4
kg.cm²
gm.cm²
gm.cm3
Correct Answer :
C. gm.cm²
Related Questions
In a lifting machine with efficiency 60%, an effort of 200 N is required to raise a load of 6 kN. The velocity ratio of the machine is
30
50
60
80
The resultant of two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P. Then,
P = R
Q = R
P = Q
None of the above is correct
Impulse can be obtained from a
Force-displacement diagram
Force-time diagram
Velocity-time diagram
Velocity-displacement diagram
In which of the following trusses, the method of substitution is required for determining the forces in all the members of the truss by graphic statics?
Howe truss
King post truss
Fink truss
Warren truss
A bullet weighing 200 g is fired horizontally with a velocity of 25 m/sec from a gun carried on a carriage which together with the gun weighs 100 kg. The velocity of recoil of the gun, will be
0.01 m/sec
0.05 m/sec
1.00 m/sec
1.5 m/see
The centre of gravity of a trapezoidal dam section whose top width is a, bottom width is band the vertical side is a, from its vertical face is
(a² + ab + b²)/3 (a + b)
(b² + bc + c²)/3 (b + c)
(a² + ab + c²)/3 (a + c)
None of these
A body A of mass 6.6 kg which is lying on a horizontal platform 4.5 m from its edge is connected to the end of a light string whose other end is supporting a body of mass 3.2 kg as shown in below figure. If the friction between the platform and the body A is 1/3, the acceleration is 
0.5 m/sec2
0.75 m/sec2
1.00 m/sec2
1.25 m/sec2
For perfectly elastic bodies, the value of coefficient of restitution is
Zero
0.5
1.0
Between 0 and 1
The apparent weight of a man in a moving lift is less than his real weight when it is going down with
Uniform speed
An acceleration
Linear momentum
Retardation
If v and ω are linear and angular velocities, the centripetal acceleration of a moving body along the circular path of radius r, will be
r/v²
v²/r
r/ω²
ω²/r
A glass ball is shot to hit a wall from a point on a smooth floor. If the ball returns back to the point of projection in twice the time taken in reaching the wall, the coefficient of restitution between the glass ball and the wall is
0.25
0.33
0.40
0.50
The angles between two forces to make their resultant a minimum and a maximum respectively are
0° and 90°
180° and 90°
90° and 180°
180° and 0°
Power can be expressed as
Work/energy
Work/time
Work × time
Work/distance
Periodic time of a particle moving with simple harmonic motion is the time taken by the particle for
Half oscillation
Quarter oscillation
Complete oscillation
None of these
A load of 500 kg was lifted through a distance of 13 cm. by an effort of 25 kg which moved through a distance of 650 cm. The efficiency of the lifting machine is
50 %
40 %
55 %
30 %
One end of a light string 4 m in length is fixed to a point on a smooth wall and the other end fastened to a point on the surface of a smooth sphere of diameter 2.25 m and of weight 100 kg. The tension in the string is
17.5 kg
19.5 kg
22.5 kg
25 kg
For a self-locking machine, the efficiency should be
Less than 60%
50 %
More than 50%
None of these
A particle moves along a straight line such that distance x traversed in t seconds is given by x = t2(t + 1), the acceleration of the particle, will be
3t3 - 2t
3t2 + 2t
6t - 2
6t + 2
The velocity of a body fallen from height h, on reaching the ground is given by
v = 2gh
v = 2gh2
v = √(2gh)
v = 1/√(2gh)
The C.G. of a right circular cone lies on its axis of symmetry at a height of
h/2
h/3
h/4
h/5
Pick up the incorrect statement from the following. In a simple harmonic motion
Velocity is maximum at its mean position
Velocity is minimum at the end of the stroke
Acceleration is minimum at the end of the stroke
Acceleration is zero at the mean position
For a non-concurrent force system to be in equilibrium
Only the closure of force polygon is sufficient
Only the closure of funicular polygon is sufficient
Both force polygon and funicular polygon must close
None of the above
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 intersection 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
Energy may be defined as
Power of doing work
Capacity of doing work
Rate of doing work
All the above
The moment of inertia of a triangular section (base b, height h) about centroidal axis parallel to the base, is
b3h/12
bh3/3
bh3/36
bh3/2
A bullet weighing 10 gm moves with a velocity of l km/sec. Its kinetic energy is (i) 5000 Nm (ii) 5000 kg.m (iii) 5000 J The correct answer is
Only (ii)
Both (i) and (iii)
Both (ii) and (iii)
All (i), (ii) and (iii)
Minimum potential energy of a system will be in the position of
Stable equilibrium
Unstable equilibrium
Neutral equilibrium
All of the above
Three forces which act on a rigid body to keep it in equilibrium. The forces must be coplanar and
Concurrent
Parallel
Concurrent parallel
None of these
The centre of gravity of a plane lamina will not be at its geometrical centre if it is a
Circle
Equilateral triangle
Rectangle
Right angled triangle
In the structure shown in below figure, the member which carries zero force, is 
AB
BC
BE
All the above