The characteristic of a couple is:
Algebraic sum of forces, constituting a couple is zero
Algebraic sum of moments of forces, constituting a couple, about any point, is same
A couple can be never the balanced by a single force
All the above
Correct Answer :
D. All the above
Related Questions
The Centre of gravity of a 10 × 15 × 5 cm T-section from its bottom, is
7.5 cm
5.0 cm
8.75 cm
7.85 cm
P is the force acting on a body whose mass is m and acceleration is f. The equation P - mf= 0, is known as
Equation of dynamics
Equation of dynamic equilibrium
Equation of statics
None of these
The mechanical advantage of an ideal machine is 100. For moving the local through 2 m, the effort moves through
0.02 m
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2.5 m
20 m
The ratio of the speed of a rolling cylinder to the speed of sliding cylinder is
Less than 1
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Between 1 and 2
Greater than 2
A light rope is loaded with many equal weights at equal horizontal intervals. The points of suspension on the rope lie on a
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Catenary
Cycloid
Ellipse
The bending moment in an arch is proportional to
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Vertical ordinate of the arch
Intercept between the arch axis and the funicular polygon
None of these
Newton's law of Collision of elastic bodies states that when two moving bodies collide each other, their velocity of separation
Is directly proportional to their velocity of approach
Is inversely proportional to their velocity of approach
Bears a constant ratio to their velocity of approach
Is equal to the sum of their velocities of approach
A point subjected to a number of forces will be in equilibrium, if
Sum of resolved parts in any two directions at right angles, are both zero
Algebraic sum of the forces is zero
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Algebraic sum of the moments of the forces about the point is zero
If the kinetic energy and potential energy of a simple harmonic oscillator of amplitude A are both equal to half the total energy, then the displacement is equal to
A
A/2
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If v and ω are linear and angular velocities, the centripetal acceleration of a moving body along the circular path of radius r, will be
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(1/2π) √(α/θ)
4π √(α/θ)
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If the horizontal range is 2.5 times the greatest height, the angle of projection of the projectile, is
57°
58°
59°
60°
The potential energy of a particle falling through a straight shaft drilled through the earth (assumed homogenous and spherical) is proportional to
log r
r
r²
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Weight
Mass
Inertia
Momentum
A projectile is thrown at an angle α to the horizontal with velocity v. It will have the maximum centripetal acceleration
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At the top of the trajectory
As it strikes the ground
Elsewhere
If the angular distance, 0 = 2t3 - 3t², the angular acceleration at t = 1 sec. is
1 rad/sec²
4 rad/sec²
6 rad/sec²
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The graphical method of determining the forces in the members of a truss is based on
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Method of section
Either method
None of the two methods
The angular speed of a car taking a circular turn of radius 100 m at 36 km/hr will be
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10 rad/sec
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King post truss
Fink truss
Warren truss
The member which does not carry zero force in the structure shown in below figure, is
ED
DC
BC
BD
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At the centre of gravity of the body
On the periphery of the body
On any point on the line of action of the force
At any point on the surface normal to the line of action of the force
The beam shown in below figure is supported by a hinge at A and a roller at B. The reaction RA of the hinged support A of the beam, is 
10.8 t
10.6 t
10.4 t
10.2 t
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Virtual centre
Instantaneous centre
Instantaneous axis
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f = g
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f = g cos θ
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32 t
4 t
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8000 km per hour
9000 km per hour
11,000 km per hour
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1/2 T
√2 T
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Less than 60%
50 %
More than 50%
None of these
A rod 5 m in length is moving in a vertical plane. When it is inclined at 60° to horizontal, its lower end is moving horizontally at 3 m/sec and upper end is moving in vertical direction. The velocity of its upper end, is
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1.0 m/sec
1.5 m/sec
2.5 m/sec
A uniform pyramid and a uniform prism of same height lie with their base on the surface. Which is more stable?
Pyramid
Prism
Both equally stable
None of the above