A particle inside a hollow sphere of radius r, having coefficient of friction μ can rest up to height of
r/2
r/A
r/3
0.134 r
Correct Answer :
D. 0.134 r
Related Questions
The resultant of two forces P and Q (such that P > Q) acting along the same straight line, but in opposite direction, is given by
P + Q
P - Q
P / Q
Q / P
Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its vertex and parallel to the base, is __________ than that passing through its C.G. and parallel to the base.
Nine times
Six times
Four times
Two times
In a framed structure, as shown in the below figure, the force in the member AB is __________ the force in member AC. 
Half
Equal to
Double
None of these
The slope on the road surface generally provided on the curves is known as
Angle of friction
Angle of repose
Angle of banking
None of these
Two bodies of masses m1 and m2 are hung from the ends of a rope, passing over a frictionless pulley as shown in the figure below. The acceleration of the string will be 
g (m1 - m2)/(m1 + m2)
2g (m1 - m2)/(m1 + m2)
g (m1 + m2)/(m1 - m2)
2g (m1 + m2)/(m1 - m2)
Frictional force encountered after commencement of motion is called
Limiting friction
Kinematic friction
Frictional resistance
Dynamic friction
The ideal angle of banking provided on the curves on roads depends upon
Weight of the vehicle
(Velocity)2 of the vehicle
Nature of the road surface
Coefficient of friction between the road and vehicle contact point
The forces, which meet at one point, but their lines of action do not lie in a plane, are called
Coplanar non-concurrent forces
Non-coplanar concurrent forces
Non-coplanar non-concurrent forces
Intersecting forces
A force while acting on a body may
Change its motion
Balance the forces, already acting on it
Give rise to the internal stresses in it
All of these
Moment of inertia of a hollow circular section, as shown in the below figure about an axis perpendicular to the section, is __________ than that about X-X axis. 
Two times
Same
Half
None of these
Centre of gravity of a solid cone lies on the axis at the height
One fourth of the total height above base
One third of the total height above base
One-half of the total height above base
Three eighth of the total height above the base
Which of the following is not the unit of work, energy and heat?
kcal
kg-m
kW-hr
h.p
The linear acceleration (a) of a body rotating along a circular path of radius (r) with an angular acceleration of α rad/s2, is
a = α/ r
a = α.r
a = r / α
None of these
When a person, on a bicycle, drives round a curve, he has to lean __________ to maintain equilibrium.
Inward
Outward
Towards front
Towards back
A framed structure is imperfect, if the numbers of members are __________ (2j - 3).
Equal to
Less than
Greater than
Either (B) or (C)
If tension in the cable supporting a lift moving downwards is half the tension when it is moving upwards, the acceleration of the lift is
g/2
g/3
g/4
None of these
Which is the correct statement about law of polygon of forces?
If any number of forces acting at a point can be represented by the sides of a polygon taken in order, then the forces are in equilibrium
If any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon, then the forces are in equilibrium
If a polygon representing forces acting at a point is closed then forces are in equilibrium
If any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon taken in order, then the forces are in equilibrium
One joule is equal to
0.1 N-m
1 N-m
10 N-m
100 N-m
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
The maximum acceleration of a particle moving with simple harmonic motion is
ω
ωr
ω2r
ω/r
In order to double the period of simple pendulum, the length of the string should be
Halved
Doubled
Quadrupled
None of these
The velocity of a particle moving with simple harmonic motion is __________ at the mean position.
Zero
Minimum
Maximum
None of these
The efficiency of a lifting machine is the ratio of
Output to the input
Work done by the machine to the work done on the machine
Mechanical advantage to the velocity ratio
All of the above
A force acting on a body may
Change its motion
Balance the other forces acting on it
Retard its motion
All of the above
A screw jack used for lifting the loads is
A reversible machine
A non-reversible machine
An ideal machine
None of these
Which of the following are vector quantities?
Linear displacement
Linear velocity
Linear acceleration
All of these
The moment of the force P about O as shown in the below figure is 
P × OA
P × OB
P × OC
P × AC
The velocity ratio for the third system of pulleys is
n
n²
2n
2n - 1
Least force required to draw a body up the inclined plane is W sin (plane inclination + friction angle) applied in the direction
Along the plane
Horizontally
Vertically
At an angle equal to the angle of friction to the inclined plane
Kinetic friction is the
Tangent of angle between normal reaction and the resultant of normal reaction and the 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