Moment of inertia of a rectangular section having width (b) and depth (d) about an axis passing through its C.G. and parallel to the width (b), is
db³/12
bd³/12
db³/36
bd³/36
Correct Answer :
B. bd³/12
Related Questions
In a single threaded worm and worm wheel, the number of teeth on the worm is 50. The diameter of the effort wheel is 100 mm and that of load drum is 50 mm. The velocity ratio is
50
100
200
400
In the equation of virtual work, following force is neglected
Reaction of any smooth surface with which the body is in contact
Reaction of a rough surface of a body which rolls on it without slipping
Reaction at a point or an axis, fixed in space, around which a body is constrained to turn
All of the above
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Weight of the vehicle
(Velocity)2 of the vehicle
Nature of the road surface
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A trolley wire weighs 1.2 kg per meter length. The ends of the wire are attached to two poles 20 meters apart. If the horizontal tension is 1500 kg find the dip in the middle of the span
2.5 cm
3.0 cm
4.0 cm
5.0 cm
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Kilogram
Newton
Watt
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Limiting friction
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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 statement is correct?
The kinetic energy of a body during impact remains constant.
The kinetic energy of a body before impact is equal to the kinetic energy of a body after impact.
The kinetic energy of a body before impact is less than the kinetic energy of a body after impact.
The kinetic energy of a body before impact is more than the kinetic energy of a body after impact.
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Second moment of area
Second moment of mass
All of these
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n
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Mechanical advantage is equal to velocity ratio
Mechanical advantage is less than velocity ratio
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Lie
Do not lie
Either A or B
None of these
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P + m.a = 0
P - m.a = 0
P × m.a = 0
P/m.a = 0
When two elastic bodies collide with each other,
The two bodies will momentarily come to rest after collision
The two bodies tend to compress and deform at the surface of contact
The two bodies begin to regain their original shape
All of the above
In ideal machines, mechanical advantage is __________ velocity ratio.
Equal to
Less than
Greater than
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The maximum velocity of a particle moving with simple harmonic motion is
ω
ωr
ω2r
ω/r
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Equal to
Less than
Greater than
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Angle of repose
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Half
Equal to
Double
None of these
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Sum of resolved parts in the vertical direction is zero (i.e. ΣV = 0)
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1 joule/s
10 joules/s
100 joules/s
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Buckling or shear
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Upward at its upper end
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Halved
Doubled
Quadrupled
None of these
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g/2
g/3
g/4
None of these
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Balance each other
Produce a couple and an unbalanced force
Are equivalent
Cannot balance each other