In ideal machines
Mechanical advantage is greater than velocity ratio
Mechanical advantage is equal to velocity ratio
Mechanical advantage is less than velocity ratio
Mechanical advantage is unity
Correct Answer :
B. Mechanical advantage is equal to velocity ratio
Related Questions
The velocity ratio of a first system of pulleys with 4 pulleys is
4
8
16
20
The range of projectile (R) on an upward inclined plane is
g. cos² β/2u². sin (α + β). cos α
2u². sin (α + β). cos α/g. cos² β
g. cos² β/2u². sin (α - β). cos α
2u². sin (α - β). cos α/g. cos² β
Moment of inertia of a triangular section of base (b) and height (h) about an axis through its base, is
bh3/4
bh3/8
bh3/12
bh3/36
The unit of work in S.I. units is
Newton
erg
kg-m
joule
The bodies which rebound after impact are called
Inelastic bodies
Elastic bodies
Neither elastic nor inelastic bodies
None of these
Which of the following is an equation of linear motion? (where, u and v = Initial and final velocity of the body, a = Acceleration of the body, and s = Displacement of the body in time t seconds.)
v = u + a.t
s = u.t + ½ a.t2
v2 = u2 + 2a.s
All of these
The resolved part of the resultant of two forces inclined at an angle θ in a given direction is equal to
The algebraic sum of the resolved parts of the forces in the given direction
The sum of the resolved parts of the forces in the given direction
The difference of the forces multiplied by the cosine of θ
The sum of the forces multiplied by the sine of θ
A pendulum which executes one beat per second is known as
Simple pendulum
Compound pendulum
Torsional pendulum
Second's pendulum
The resultant of the following three couples 20 kg force, 0.5 m arm, +ve sense 30 kg force, 1 m arm, -ve sense 40 kg force, 0.25 m arm, +ve sense having arm of 0.5 m will be
20 kg, -ve sense
20 kg, + ve sense
10 kg, + ve sense
10 kg, -ve sense
The moment of a force
Is the turning effect produced by a force, on the body, on which it acts
Is equal to the product of force acting on the body and the perpendicular distance of a point and the line of action of the force
Is equal to twice the area of the triangle, whose base is the line representing the force and whose vertex is the point, about which the moment is taken
All of the above
The unit of power in S.I. units is
Horsepower
Joule
Watt
kg-m
The centre of gravity of a trapezium with parallel sides a and b lies at a distance of y from the base b, as shown in the below figure. The value of y is 
h [(2a + b)/(a + b)]
(h/2) [(2a + b)/(a + b)]
(h/3) [(2a + b)/(a + b)]
(h/3) [(a + b)/(2a + b)]
If the gravitational acceleration at any place is doubled, then the weight of a body will be
g/2
g
√2.g
2g
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)
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
The unit of angular acceleration is
N-m
m/s
m/s2
rad/s2
The motion of a wheel of a car is
Purely translation
Purely rotational
Combined translation and rotational
None of these
For any system of coplanar forces, the condition of equilibrium is that the
Algebraic sum of the horizontal components of all the forces should be zero
Algebraic sum of the vertical components of all the forces should be zero
Algebraic sum of moments of all the forces about any point should be zero
All of the above
A body of weight W is required to move up on rough inclined plane whose angle of inclination with the horizontal is α. The effort applied parallel to the plane is given by (where μ = tanφ = Coefficient of friction between the plane and the body.)
P = W tanα
P = W tan (α + φ)
P = W (sinα + μcosα)
P = W (cosα + μsinα)
Mass moment of inertia of a uniform thin rod of mass M and length (l) about its mid-point and perpendicular to its length is
(2/3) Ml2
(1/3) Ml2
(3/4) Ml2
(1/12) Ml2
The moment of inertia of a thin spherical shell of mass m and radius r, about its diameter is
mr2/3
2mr2/3
2mr2/5
3mr2/5
The coefficient of friction depends on
Area of contact
Shape of surfaces
Strength of surfaces
Nature of surface
According to law of triangle of forces
Three forces acting at a point will be in equilibrium
Three forces acting at a point can be represented by a triangle, each side being proportional to force
If three forces acting upon a particle are represented in magnitude and direction by the sides of a triangle, taken in order, they will be in equilibrium
If three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two
According to parallel axis theorem, the moment of inertia of a section about an axis parallel to the axis through centre of gravity (i.e. IP) is given by(where, A = Area of the section, IG = Moment of inertia of the section about an axis passing through its C.G., and h = Distance between C.G. and the parallel axis.)
IP = IG + Ah2
IP = IG - Ah2
IP = IG / Ah2
IP = Ah2 / IG
The C.G. of a right circular solid cone of height h lies at the following distance from the base
h/2
J/3
h/6
h/4
When the spring of a watch is wound, it will possess
Strain energy
Kinetic energy
Heat energy
Electrical energy
In a screw jack, the effort required to lower the load is __________ the effort required to raise the same load.
Less than
Equal to
More than
None of these
Static friction is always __________ dynamic friction.
Equal to
Less than
Greater than
None of these
The efficiency of a screw jack is maximum, when (where α = Helix angle, and φ = Angle of friction.)
α = 45° + φ/2
α = 45° - φ/2
α = 90° + φ
α = 90° - φ
Coplanar concurrent forces are those forces which
Meet at one point, but their lines of action do not lie on the same plane
Do not meet at one point and their lines of action do not lie on the same plane
Meet at one point and their lines of action also lie on the same plane
Do not meet at one point, but their lines of action lie on the same plane