A cube on a smooth horizontal surface
Cannot be in stable equilibrium
Cannot be in neutral equilibrium
Cannot be in unstable equilibrium
Can be in any of these states
Correct Answer :
D. Can be in any of these states
Related Questions
A disc of mass 4 kg, radius 0.5 m and moment of inertia 3 kgm² rolls on a horizontal surface so that its center moves with speed 5 m/see. Kinetic energy of the disc is
50 J
150 J
200 J
400 J
A heavy ladder resting on floor and against a vertical wall may not be in equilibrium if
Floor is smooth and wall is rough
Floor is rough and wall is smooth
Both floor and wall are rough
Both floor and wall are smooth
A projectile is thrown at an angle α to the horizontal with velocity v. It will have the maximum centripetal acceleration
At the start
At the top of the trajectory
As it strikes the ground
Elsewhere
Minimum potential energy of a system will be in the position of
Stable equilibrium
Unstable equilibrium
Neutral equilibrium
All of the above
An ordinate in a funicular polygon represents
Shear force
Resultant force
Bending moment
Equilibrium
If two equal forces of magnitude P act at an angle θ, their resultant, will be
P cos θ/2
2P sin θ/2
P tan θ/2
2P cos θ/2
The units of moment of inertia of an area are
kg/m
kg/m2
m4
m3
The centre of gravity of a quadrant of a circle lies along its central radius at a distance of
0.2 R
0.4 R
0.3 R
0.6 R
Periodic time of body moving with simple harmonic motion, is
Directly proportional to its angular velocity
Directly proportional to the square of its angular velocity
Inversely proportional to the square of its angular velocity
Inversely proportional to its angular velocity
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
The equation of motion of a particle starting from rest along a straight line is x = t3 - 3t2+ 5. The ratio of the accelerations after 5 sec and 3 sec will be
2
3
4
5
The point about which combined motion of rotation and translation of a rigid body takes place, is known as
Virtual centre
Instantaneous centre
Instantaneous axis
Point of rotation
The force polygon representing a set of forces in equilibrium is a
Triangle
Open polygon
Closed polygon
Parallelogram
The gravitational force makes a satellite go round the earth in a circular orbit, if it is projected with an initial velocity of
8.04 km/sec at a height of 285 km
11.11 km/sec at a height of 37,400 km
11.26 km/sec, the satellite escapes the pull of the earth
All the above
A particle moving with a simple harmonic motion, attains its maximum velocity when it passes
The extreme point of the oscillation
Through the mean position
Through a point at half amplitude
None of these
The moment of inertia of a hollow circular section whose external diameter is 8 cm and internal diameter is 6 cm, about centroidal axis, is
437.5 cm4
337.5 cm4
237.5 cm4
137.5 cm4
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
The angle of friction is:
The ratio of the friction and the normal reaction
The force of friction when the body is in motion
The angle between the normal reaction and the resultant of normal reaction and limiting friction
The force of friction at which the body is just about to move
The potential energy of a particle falling through a straight shaft drilled through the earth (assumed homogenous and spherical) is proportional to
log r
r
r²
1/r Where r is the distance of the particle from centre of the earth
A stone was thrown vertically upwards from the ground with a velocity of 50 m/sec. After 5 seconds another stone was thrown vertically upwards from the same place. If both the stones strike the ground at the same time, then the velocity with which the second stone was thrown should be (Assume g = 10 m/sec²)
15 m/sec
25 m/sec
40 m/sec
50 m/sec
A stone is whirled in a vertical circle, the tension in the string, is maximum
When the string is horizontal
When the stone is at the highest position
When the stone is at the lowest position
At all the positions
A cable loaded with 10 kN/m of span is stretched between supports in the same horizontal line 100 m apart. If the central dip is 10 m, then the maximum and minimum pull in the cable respectively are
1346.3 kN and 1500 kN
1436.2 kN and 1250 kN
1346.3 kN and 1250 kN
1436.2 kN and 1500 kN
Principle of Transmissibility of Forces states that, when a force acts upon a body, its effect is
Maximum if it acts at the centre of gravity of the body
Different at different points on its line of
Same at every point on its line of action
Minimum if it acts at the C.G. of the body
A sphere is resting on two planes BA and BC which are inclined at 45° and 60° respectively with the horizontal. The reaction on the plane BA will be
Less than that on BC
More than that of BC
Equal to that on BC
None of these
The acceleration of a particle moving along the circumference of a circle with a uniform speed, is directed
Radially
Tangentially at that point
Away from the centre
Towards the centre
The frequency of oscillation on moon as compared to that on earth, will be
2.44 times more
2.44 times less
3 times less
3 times more
A body is said to move with Simple Harmonic Motion if its acceleration, is
Always directed away from the centre, the point of reference
Proportional to the square of the distance from the point of reference
Proportional to the distance from the point of reference and directed towards it
Inversely proportion to the distance from the point of reference
Cartesian form of the equation of catenary is
y = c cosh x/c
y = c sinh x/c
y = c tan x/c
y = c sin x/c
A uniform pyramid and a uniform prism of same height lie with their base on the surface. Which is more stable?
Pyramid
Prism
Both equally stable
None of the above
The member forces in a statically in determinate truss
Can be obtained by graphic statics
Cannot be obtained by graphic statics
May be obtained by graphic statics
Can be obtained by graphic statics by trial and error