A square hole is punched out of a circular lamina, the diagonal of the square being the radius of the circle. If r is the radius of the circle, the C.G. of the remainder from the corner of the square on the circumference will be
[r (π + 0.25)]/(π - 0.5)
[r (π - 0.5)]/(π + 0.25)
[r (π - 0.25)]/(π - 0.5)
[r (π + 0.25)]/(π + 0.5)
Correct Answer :
C. [r (π - 0.25)]/(π - 0.5)
Related Questions
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Dyne
Newton
Joule
Erg
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
A/√2
A√2
0.For maximum range of a projectile, the angle of projection should be
30°
45°
60°
None of these
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2πNT /60 watts
All the above
The centre of gravity of the trapezium as shown in below figure from the side is at a distance of
(h/3) × [(b + 2a)/(b + a)]
(h/3) × [(2b + a)/(b + a)]
(h/2) × [(b + 2a)/(b + a)]
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On a mass m describing a circular path of radius r, the centrifugal force
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Acts towards the centre of rotation
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Must be decreased
Must be increased
Is not changed but weight of the bob is increased
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Dyne in absolute units
Newton and dyne in absolute units
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tan θ
cosec θ
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106 dyne
107 dyne
108 dyne
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The acceleration of a train starting from rest at any instant is 1/6(V + 1) m/sec² where V is the velocity of the train in m/sec. The train will attain a velocity of 36 km/hour after travelling a distance of
2000 m
2100 m
2200 m
2300 m
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'
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9.3 m/sec
8.3 m/sec
7.3 m/sec
6.3 m/sec
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Cycloid
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Isolated joint with all the forces, internal as well as external, acting on it
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h/3
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h/5
The mechanical advantage of an ideal machine is 100. For moving the local through 2 m, the effort moves through
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2.5 m
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45°
60°
90°
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m4
m3
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99.4 cm
100 cm
101 cm
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Half the original velocity in the opposite direction
Original velocity in the opposite direction
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ω2 (l sin + r cos φ tan θ)
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Force × velocity
Force × acceleration
None of these
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To be maximum
To be minimum
None of these
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P + Q
P/Q
Q/P
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