The moment of inertia of a square of side a about its diagonal is
a2/8
a3/12
a4/12
a4/16
Correct Answer :
C. a4/12
Related Questions
The angular velocity (in rad/s) of a body rotating at N revolutions per minute is
πN/60
πN/180
2πN/60
2πN/180
In ideal machines, mechanical advantage is __________ velocity ratio.
Equal to
Less than
Greater than
None of these
The linear velocity of a body rotating at ω rad/s along a circular path of radius r is given by
ω/r
ω.r
ω2/r
ω2.r
The velocity of a particle moving with simple harmonic motion is __________ at the mean position.
Zero
Minimum
Maximum
None of these
The units of moment of inertia of mass are
kg-m²
m²/kg.
kg/m²
kg/m
The acceleration of a particle moving with simple harmonic motion is __________ at the mean position.
Zero
Minimum
Maximum
None of these
Angle of friction is the
Angle between normal reaction and the resultant of normal reaction and the limiting friction
Ratio of limiting friction and normal reaction
The ratio of minimum friction force to the friction force acting when the body is just about to move
The ratio of minimum friction force to friction force acting when the body is in motion
Moment of inertia of a hollow rectangular section as shown in the below figure about X-X axis, is 
(BD³/12) - (bd³/12)
(DB³/12) - (db³/12)
(BD³/36) - (bd³/36)
(DB³/36) - (db³/36)
According to Newton's first law of motion,
Everybody continues in its state of rest or of uniform motion, in a straight line, unless it is acted upon by some external force
The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction, in which the force acts
To every action, there is always an equal and opposite reaction
None of the above
A block of mass 20 kg lying on a rough horizontal plane is connected by a light string passing over a smooth pulley to another mass 5 kg, which can move freely in the Vertical direction, as shown in the below figure. The tension in the string will __________ with the increase in coefficient of friction. 
Increase
Decrease
Not be effected
None of these
Which of the following do not have identical dimensions?
Momentum and impulse
Torque and energy
Torque and work
Moment of a force and angular momentum.
Static friction is always __________ dynamic friction.
Equal to
Less than
Greater than
None of these
A framed structure is imperfect, if the numbers of members are __________ (2j - 3).
Equal to
Less than
Greater than
Either (B) or (C)
The coefficient of friction depends on
Area of contact
Shape of surfaces
Strength of surfaces
Nature of surface
If a rigid body is in equilibrium under the action of three forces, then
These forces are equal
The lines of action of these forces meet in a point
The lines of action of these forces are parallel
Both (B) and (C) above
The range of projectile will be maximum for a given velocity of projectile, when the angle of projection (α) is
β/2
30° + β/2
45° + β/2
60° + β/2
The unit of force in S.I. system of units is
Dyne
Kilogram
Newton
Watt
If the gravitational acceleration at any place is doubled, then the weight of a body will be
g/2
g
√2.g
2g
The velocity of a particle (v) moving with simple harmonic motion, at any instant is given by (where r = Amplitude of motion, and y = Displacement of the particle from mean position.)
ω.√(y² - r²)
ω.√(r² - y²)
ω².√(y² - r²)
ω².√(r² - y²)
The time of flight of a projectile on downward inclined plane depends upon
Angle of projection
Angle of inclination of the plane
Both (A) and (B)
None of these
The forces which do not meet at one point and their lines of action do not lie on the same plane are known as
Coplanar concurrent forces
Coplanar non-concurrent forces
Non-coplanar concurrent forces
None of these
Center of percussion is
The point of C.G.
The point of metacenter
The point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis
Point of suspension
Limiting force of friction is the
Tangent of angle between normal reaction and the resultant of normal reaction and limiting friction
Ratio of limiting friction and normal reaction
The friction force acting when the body is just about to move
The friction force acting when the body is in motion
The motion of a particle round a fixed axis is
Translatory
Rotary
Circular
Translatory as well as rotary
When a person, on a bicycle, drives round a curve, he has to lean __________ to maintain equilibrium.
Inward
Outward
Towards front
Towards back
Two balls of equal mass and of perfectly elastic material are lying on the floor. One of the balls with velocity v is made to strike the second ball. Both the balls after impact will move with a velocity
v
v/2
v/4
v/8
Which of the following is not a vector quantity?
Weight
Velocity
Acceleration
Force
The centre of gravity of a quadrant of a circle lies along its central radius (r) at a distance of
0.5r
0.6 r
0.7 r
0.8 r
In a framed structure, as shown in the below figure, the forces in the members AB and BC are respectively 
√3. W (tensile) and 2W (compressive)
2W (tensile) and √3. W (compressive)
2√3. W (tensile) and 2√3. W (compressive)
None of the above
The horizontal range of a projectile (R) is given by
R = u² cos2α/g
R = u² sin2α/g
R = u² cosα/g
R = u² sinα/g