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
Correct Answer :
D. 2000 metres
Related Questions
The moment of inertia of a hollow circular section whose external diameter is 8 cm and internal diameter is 6 cm, about centroidal axis, is
437.5 cm4
337.5 cm4
237.5 cm4
137.5 cm4
The condition of equilibrium for any system of forces in a plane is
That polygon of forces must close
That resultant couple must be zero
Both (A) and (B)
None of the above
The maximum velocity of a body vibrating with a simple harmonic motion of amplitude 150 mm and frequency 2 vibrations/sec, is
188.5 m/sec
18.85 m/sec
1.885 m/sec
0.18845 m/sec
The velocity of a moving body, is
A vector quantity
A scalar quantity
A constant quantity
None of these
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 block of weight 50 kg is placed on a horizontal plane. When a horizontal force of 18 kg is applied, the block is just on the point of motion. The angle of friction is
17° 48'
18° 48'
19° 48'
20° 48'
The inherent property of a body which offers reluctance to change its state of rest or uniform motion, is
Weight
Mass
Inertia
Momentum
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
A rigid body is in a stable equilibrium if the application of any force
Can raise the CG of the body but cannot lower it
Tends to lower the CG of the body
Neither raises nor lowers the CG of the body
None of above
If two forces P and Q (P > Q) act on the same straight line but in opposite direction, their resultant, is
P + Q
P/Q
Q/P
P - Q
A pilot flies a small plane in a vertical loop of radius r. At the top of its trajectory he experiences weightlessness. If the acceleration due to gravity is g, the speed of the plane at the top of its trajectory would be
Zero
Infinite
gr
2gr
For the given values of initial velocity of projection and angle of inclination of the plane, the maximum range for a projectile projected upwards will be obtained, if the angle of projection is
α = π/4 - β/2
α = π/2 + β/2
α = β/2 - π/2
α = π/4 - β/2
If two forces are in equilibrium, then the forces must (i) Be equal in magnitude (ii) Be opposite in sense (iii) Act along the same line The correct answer is
(i) and (ii)
(i) and (iii)
Only (i)
All (i), (ii) and (iii)
The product of mass and velocity of a moving a body, is called
Moment
Momentum
Power
Impulse
The moment of inertia of the shaded portion of the area shown in below figure about the X-axis, is
229.34 cm4
329.34 cm4
429.34 cm4
529.34 cm4
From the circular plate of a diameter 6 cm is cut out a circular plate whose diameter is equal to radius of the plate. The C.G. of the remainder shifts from the original position through
0.25 cm
0.50 cm
0.75 cm
1.00 cm
Two shots fired simultaneously from the top and bottom of a vertical tower with elevations of 30° and 45° respectively strike a target simultaneously. If horizontal distance of the target from the tower is 1000 m, the height of the tower is
350 m
375 m
400 m
425 m
If the angle between the applied force and the direction of motion of a body, is between 90° and 180°, the work done, is called
Virtual work
Imaginary work
Zero work
Negative work
A ball of mass 1 kg moving with a velocity of 2 m/sec collides a stationary ball of mass 2 kg and comes to rest after impact. The velocity of the second ball after impact will be
Zero
0.5 m/sec
1.0 m/sec
2.0 m/sec
For a simple pendulum, the period of one oscillation is
2π √(l/2g)
2π √(2g/l)
2π √(l/g)
2π √(g/2l)
Pick up the incorrect statement from the following. In case of suspension bridge due to rise in temperature,
Dip of the cable increases
Length of the cable increases
Dip of the cable decreases
None of these
The member which does not carry zero force in the structure shown in below figure, is
ED
DC
BC
BD
A spring scale in a stationary lift shows a reading of 60 kg for a man standing on it. If the lift starts descending at an acceleration of g/5, the scale reading would be
48 kg
60 kg
72 kg
None of these
A particle is dropped from the top of a tower 60 m high and another is projected upwards from the foot of the tower to meet the first particle at a height of 15.9 m. The velocity of projection of the second particle is
16 m/sec
18 m/sec
20 m/sec
22 m/sec
Equation of motion of a point in a straight line, is
v = u + ft
S = ut + ½ ft2
2fS = v2 - u2
All the above
The reaction at the central support B of the beam ABC hinged at D shown in below figure is 
2 t
5.8 t
0.2 t
3.5 t
When a body falls freely under gravitational force, it possesses
Maximum weight
Minimum weight
No weight
No effect on its weight
A string of length 90 cm is fastened to two points A and B at the same level 60 cm apart. A ring weighing 120 g is slided on the string. A horizontal force P is applied to the ring such that it is in equilibrium vertically below B. The value of P is:
40 g
60 g
80 g
100 g
The moment of inertia of a circular lamina of diameter d, about an axis perpendicular to the plane of the lamina and passing through its centre, is
πd4/12
πd4/16
πd4/24
πd4/32
The reaction at the support D of the continuous beam ABCD, hinged at two points shown in below figure is 
1.6 t
1.6 t ↓
0.5 t
0.5 t ↓