The forces which meet at one point, but their lines of action __________ on the same plane, are Known as non-coplanar concurrent forces.
Lie
Do not lie
Either A or B
None of these
Correct Answer :
B. Do not lie
Related Questions
Pick up the incorrect statement from the following:
The C.G. of a circle is at its centre
The C.G. of a triangle is at the intersection of its medians
The C.G. of a rectangle is at the intersection of its diagonals
The C.G. of a semicircle is at a distance of r/2 from the centre
The point, through which the whole weight of the body acts, irrespective of its position, is known as
Moment of inertia
Centre of gravity
Centre of percussion
Centre of mass
The force required to move the body up the plane will be minimum if it makes an angle with the inclined plane __________ the angle of friction.
Equal to
Less than
Greater than
None of these
The angle between two forces when the resultant is maximum and minimum respectively are:
0° and 180°
180° and 0°
90° and 180°
90° and 0°
A force acting on a body may
Change its motion
Balance the other forces acting on it
Retard its motion
All of the above
Which of the following is not a vector quantity?
Weight
Velocity
Acceleration
Force
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 centre of gravity of a uniform lamina lies at
The centre of heavy portion
The bottom surface
The midpoint of its axis
All of the above
If a number of forces are acting at a point, their resultant is given by
(ΣV)2 + (ΣH)2
√[(ΣV)2 + (ΣH)2]
(ΣV)2 +(ΣH)2 +2(ΣV)(ΣH)
√[(ΣV)2 +(ΣH)2 +2(ΣV)(ΣH)]
The product of either force of couple with the arm of the couple is called
Resultant couple
Moment of the forces
Resulting couple
Moment of the couple
A screw jack used for lifting the loads is
A reversible machine
A non-reversible machine
An ideal machine
None of these
When a body falls freely under gravitational force, it possesses __________ weight.
No
Minimum
Maximum
None of these
In a screw jack, the effort required to lift the load is given by (where W = Load lifted, α = Helix angle, and φ = Angle of friction.)
P = W tan (α - φ)
P = W tan (α + φ)
P = W tan (φ - α)
P = W cos (α + φ)
A cable with a uniformly distributed load per horizontal meter run will take the following shape
Straight line
Parabola
Hyperbola
Elliptical
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
When trying to turn a key into a lock, following is applied
Coplanar force
Non-coplanar forces
Moment
Couple
The angle of inclination of the plane at which the body begins to move down the plane, is called
Angle of friction
Angle of repose
Angle of projection
None of these
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
If a given force (or a given system of forces) acting on a body __________ the position of the body, but keeps it in equilibrium, then its effect is to produce internal stress in the body.
Change
Does not change
Changes periodically
None of these
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)
The energy possessed by a body, for doing work by virtue of its position, is called
Potential energy
Kinetic energy
Electrical energy
Chemical energy
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
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
Which of the following is not a scalar quantity?
Mass
Volume
Density
Acceleration
The velocity ratio of a simple wheel and axle with D and d as the diameters of effort wheel and load axle, is
D + d
D - d
D × d
D / d
The principle of transmissibility of forces states that, when a force acts upon a body, its effect is
Same at every point on its line of action
Different at different points on its line of action
Minimum, if it acts at the centre of gravity of the body
Maximum, if it acts at the centre of gravity of the body
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
A flywheel on a motor goes from rest to 1000 rpm in 6 sec. The number of revolutions made is nearly equal to
25
50
100
250
Mass moment of inertia of a thin rod about its one end is __________ the mass moment of inertia of the same rod about its midpoint
Same as
Twice
Thrice
Four times
Which of the following statement is incorrect?
A force acting in the opposite direction to the motion of the body is called force of friction
The ratio of the limiting friction to the normal reaction is called coefficient of friction
A machine whose efficiency is 100% is known as an ideal machine
The velocity ratio of a machine is the ratio of load lifted to the effort applied