One end of a helical spring is fixed while the other end carries the load W which moves with simple harmonic motion. The frequency of motion is given by (where δ = Deflection of the spring)
2π. √(g/δ)
1/2π. √(g/δ)
2π. √(δ/g)
1/2π. √(δ/g)
Correct Answer :
B. 1/2π. √(g/δ)
Related Questions
The rotor of a ship rotates in clockwise direction when viewed from stern and the ship takes a left turn. The effect of gyroscopic couple acting on it will be
To raise the bow and stern
To lower the bow and stern
To raise the bow and lower the stern
To raise the stern and lower the bow
In a screw jack, the effort required to lower the load W is given by
P = W tan(α - φ)
P = W tan(α + φ)
P = W tan(φ - α)
P = W cos(α + φ)
When the primary direct crank of a reciprocating engine makes an angle of θ with the line of stroke, then the secondary direct crank will make an angle of _________ with the line of stroke.
θ/2
θ
2θ
4θ
The Whitworth quick return motion mechanism is formed in a slider crank chain when the
Coupler link is fixed
Longest link is a fixed link
Slider is a fixed link
Smallest link is a fixed link
The ratio of the driving tensions for V-belts is __________ times that of flat belts. (Where β = Semi-angle of the groove)
sinβ
cosβ
cosecβ
secβ
A body of weight W is required to move up the rough inclined plane whose angle of inclination with the horizontal is α. The effort applied parallel to the plane is given by (where μ = tan φ = Coefficient of friction between the plane and the body)
P = W tan α
P = W tan (α + φ)
P = W (sin α + μ cos α)
P = W (cos α + μ sin α)
The centre of gravity of a coupler link in a four bar mechanism will experience
No acceleration
Only linear acceleration
Only angular acceleration
Both linear and angular acceleration
In Meyer's expansion valve, the main valve is driven by an eccentric having an angle of advance from
10°-15°
15°-25°
25°-30°
30°-40°
If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the latter at the same speed will be
Four times the first one
Same as the first one
One fourth of the first one
One and a half times the first one
In vibration isolation system, if ω/ωn > 1, then the phase difference between the transmitted force and the disturbing force is
0°
90°
180°
270°
A flywheel is fitted to the crankshaft of an engine having W as the amount of indicated work per revolution and permissible limits of coefficient of fluctuation of energy and speed as CE and CS respectively. The kinetic energy of the flywheel is given by
2 W CE / CS
W CE / 2CS
W CE / CS
W CS / 2CE
The Coriolis component of acceleration acts
Along the sliding surface
Perpendicular to the sliding surface
At 45° to the sliding surface
Parallel to the sliding surface
Efficiency of a screw jack is given by
tan (α + φ)/tanα
tanα/tan (α +φ)
tan (α - φ)/tanα
tanα/tan (α - φ)
In full depth involute system, the smallest number of teeth in a pinion which meshes with rack without interference is
12
16
25
32
Which of the following is a turning pair?
Piston and cylinder of a reciprocating steam engine
Shaft with collars at both ends fitted into a circular hole
Lead screw of a lathe with nut
Ball and a socket joint
The two elements of a pair are said to form a _________ when they permit relative motion between them.
Open pair
Kinematic pair
Sliding pair
None of these
The frictional torque transmitted in a flat pivot bearing with assumption of uniform pressure is _________ as compared to uniform wear.
Less
More
Same
None of these
Effort of a governor is the
Mean force exerted at the sleeve for a given percentage change of speed
Workdone at the sleeve for maximum equilibrium speed
Mean force exerted at the sleeve for maximum equilibrium speed
None of the above
In a Hartnell governor, the lift of the sleeve is given by (where r₁ and r₂ = Max. and min. radii of rotation, x = Length of ball arm of the lever, and y = Length of sleeve arm of the lever)
(r₁ + r₂) (y/x)
(r₁ + r₂) (x/y)
(r₁ - r₂) (y/x)
(r₁ - r₂) (x/y)
The partial balancing of reciprocating parts in locomotives produces
Hammer blow
Swaying couple
Variation in tractive force along the line of stroke
All of the above
Which of the following disciplines provides study of relative motion between the parts of a machine?
Theory of machines
Applied mechanics
Mechanisms
Kinematics
The primary unbalanced force due to inertia of reciprocating parts in a reciprocating engine is given by (where m = Mass of reciprocating parts, ω = Angular speed of crank, r = Radius of crank, θ = Angle of inclination of crank with the line of stroke, and n = Ratio of the length of connecting rod to radius of crank)
m.ω².r sinθ
m.ω².r cosθ
m.ω².r (sin 2θ/n)
m.ω².r (cos 2θ/n)
When the addenda on pinion and wheel is such that the path of approach and path of recess are half of their maximum possible values, then the length of the path of contact is given by (where r = Pitch circle radius of pinion, R = Pitch circle radius of wheel, and φ = Pressure angle)
[(r² + R²) cosφ]/2
[(r² + R²) sinφ]/2
[(r + R) cosφ]/2
[(r + R) sinφ]/2
The stress induced in a body will be shear stress, when it is subjected to
Longitudinal vibrations
Transverse vibrations
Torsional vibrations
None of these
A body is said to be under forced vibrations, when
There is a reduction in amplitude after every cycle of vibration
No external force acts on a body, after giving it an initial displacement
A body vibrates under the influence of external force
None of the above
The type of pair formed by two elements which are so connected that one is constrained to turn or revolve about a fixed axis of another element is known as
Turning pair
Rolling pair
Sliding pair
Spherical pair
In a multiple V-belt drive, when a single belt is damaged, it is preferable to change the complete set to
Reduce vibration
Reduce slip
Ensure uniform loading
Ensure proper alignment
Typewriter constitutes
Machine
Structure
Mechanism
Inversion
The dynamic friction is the friction experienced by a body, when the body
Is in motion
Is at rest
Just begins to slide over the surface of the other body
None of the above
Which of the following statement is correct?
For constant velocity ratio transmission between two gears, the common normal at the point of contact must always pass through a fixed point on the line joining the centres of rotation of gears.
For involute gears, the pressure angle changes with the change in centre distance between gears.
The epicyclic gear trains involve rotation of atleast one gear axis about some other gear axis.
All of the above