One half of a vibration of a body, is called
Period time
Oscillation
Beat
Amplitude
Correct Answer :
C. Beat
Related Questions
The resultant of two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P. Then,
P = R
Q = R
P = Q
None of the above is correct
If the radius of the earth is 600 km the height of a mountain above sea level at the top of which a beat seconds pendulum at sea level, looses 27 seconds a day, is
500 metres
1000 metres
1500 metres
2000 metres
The Law of Polygon of Forces states that
If a polygon representing the forces acting at point in a body is closed, the forces are in equilibrium
If forces acting on a point can be represented in magnitude and direction by the sides of a polygon taken in order, then the resultant of the forces will be represented in magnitude and direction by the closing side of the polygon
If forces acting on a point can be represented of a polygon taken in order, their sides of a polygon taken in order, their resultant will be represented in magnitude and direction by the closing side of the polygon, taken in opposite order
If forces acting on a point can be represented in magnitude and direction by the sides of a polygon in order, the forces are in equilibrium
The angle of projection for a range is equal to the distance through which the particle would have fallen in order to acquire a velocity equal to the velocity of projection, will be
30°
45°
60°
75°
If the direction of projection bisects the angle between the vertical and the inclined plane, then the range of projectile on the inclined plane is
Zero
Maximum
Minimum
None of these
The practical units of work, is
Erg
Joule
Newton
Dyne
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
Two resolved parts in any two directions at right angles are equal
Algebraic sum of the moments of the forces about the point is zero
The C.G. of a thin hollow cone of height h, above its base lies on the axis, at a height of
h/3
h/4
2h/3
3h/4
Pick up the correct statement from the following:
Nature plays an important role in the launch of a satellite
The earth's gravity reduces the speed of a satellite by 32 km per second
The gravitational force relents as the satellite climbs higher
All the above
The acceleration of a particle moving along the circumference of a circle with a uniform speed, is directed
Radially
Tangentially at that point
Away from the centre
Towards the centre
On a ladder resting on a rough ground and leaning against a smooth vertical wall, the force of friction acts
Downwards at its upper end
Upwards at its upper end
Perpendicular to the wall at its upper end
Zero at its upper end
If α is the angular acceleration of a compound pendulum whose angular displacement is θ, the frequency of the motion is
2π √(α/θ)
(1/2π) √(α/θ)
4π √(α/θ)
2π √(α - θ)
A particle moving with a simple harmonic motion, attains its maximum velocity when it passes
The extreme point of the oscillation
Through the mean position
Through a point at half amplitude
None of these
A satellite goes on moving along its orbit round the earth due to
Gravitational force
Centrifugal force
Centripetal force
None of these
When a body moves round a fixed axis, it has
A rotary motion
A circular motion
A translatory
A rotary motion and translatory motion
In a lifting machine with efficiency 60%, an effort of 200 N is required to raise a load of 6 kN. The velocity ratio of the machine is
30
50
60
80
The condition for a lifting machine to be reversible is that its efficiency should be
Less than 50%
More than 50%
More than 66.67%
Equal to 100%
A body is dropped from a height of 100 m and at the same time another body is projected vertically upward with a velocity of 10 m/sec. The two particles will
Never meet
Meet after 1 sec
Meet after 5 sec
Meet after 10 sec
A particle of mass 2 kg executes simple harmonic motion of frequency 6/71 Hz and amplitude 0.25 m. Its maximum kinetic energy is
4.5 J
9.0 J
12.0 J
18.0 J
Two objects moving with uniform speeds are 5 m apart after 1 second when they move towards each other and are 1 m apart when they move in the same direction. The speeds of the objects are
2 m/sec and 2 m/sec
3 m/sec and 2 m/sec
3 m/sec and 3 m/sec
4 m/sec and 6 m/sec
The resultant of two forces acting at right angles is 5 kgf and if they act at an angle of 60°, it is 37 kgf. The magnitudes of the forces are:
2 kgf, 3 kgf
3 kgf, 4 kgf
4 kgf, 5 kgf
5 kgf, 3 kgf
The following is not a law of static friction:
The force of friction always acts in a direction opposite to that in which the body tends to move
The force of friction is dependent upon the area of contact
The force of friction depends upon the roughness of the surface
The magnitude of the limiting friction bears a constant ratio to the normal reaction between two surfaces
If the velocity of projection is 4 m/sec and the angle of projection is α°, the maximum height of the projectile from a horizontal plane, is
u² cos² α/2g
u² sin² α/2g
u² tan² α/2g
u² sin 2α/2g
A ladder of weight 'w' rests against a smooth vertical wall, and rests on rough horizontal ground, the coefficient of friction between the ladder and the ground being 1/4. The maximum angle of inclination of the ladder to the vertical, if a man of weight 'w' is to walk to the top of it safely, is tan'1 x, where x is
1/4
1/3
3
4
A ball moving on a smooth horizontal table hits a rough vertical wall, the coefficient of restitution between ball and wall being 1/3. The ball rebounds at the same angle. The fraction of its kinetic energy lost is
1/3
2/3
1/9
8/9
The maximum displacement of a particle executing S.H.M. corresponds to
Zero potential energy and maximum kinetic energy
Zero kinetic energy and maximum potential energy
Maximum kinetic energy and maximum potential energy
Minimum kinetic energy and minimum potential energy
A body of weight 14 g appears to weight 13 g when weighed by a spring balance in a moving lift. The acceleration of the lift at that moment was
0.5 m/sec2
0.7 m/sec2
1 m/sec2
1 cm/sec2
Total no of instantaneous centres of a machine having n links, is
n/2
n
(n - 1)
n (n - 1)/2
A satellite moves in its orbit around the earth due to
Gravitational force
Centripetal force
Centrifugal force
None of these
The angle of friction is:
The ratio of the friction and the normal reaction
The force of friction when the body is in motion
The angle between the normal reaction and the resultant of normal reaction and limiting friction
The force of friction at which the body is just about to move