If the linear velocity of a point on the rim of a wheel of 10 m diameter, is 50 m/sec, its angular velocity will be
20 rad/sec
15 rad/sec
10 rad/sec
5 rad/sec
Correct Answer :
D. 5 rad/sec
Related Questions
If two forces acting at a point are in equilibrium, they must be equal in magnitude and their line of action must be along
The same line in the same sense
The same line in opposite sense
The perpendicular to both the lines
None of these
For a given velocity of a projectile, the range is maximum when the angle of projection is
30°
45°
90°
0°
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
Work may be defined as
Force × distance
Force × velocity
Force × acceleration
None of these
If two bodies of masses M1 and M2(M1 > M2) are connected by alight inextensible string passing over a smooth pulley, the tension in the string, will be given by
T = g(M1 - M2)/(M1 + M2)
T = g(M1 + M2)/(M1 × M2)
T = g(M2 - M1)/(M1 + M2)
T = g(M2 + M1)/(M2 - M1)
Pick up the correct statement from the following. A rubber ball when strikes a wall rebounds but a lead ball of same mass and velocity when strikes the same wall, falls down
Rubber and lead balls undergo equal changes in momentum
Change in momentum suffered by lead ball is less that of rubber ball
Momentum of rubber ball is less than that of lead ball
None of these
For a particle moving with a simple harmonic motion, the frequency is
Directly proportional to periodic time
Inversely proportional to periodic time
Inversely proportional to its angular velocity
Directly proportional to its angular velocity
A simple pendulum of length l has an energy E, when its amplitude is A. If the length of pendulum is doubled, the energy will be
E
E/2
2E
4E
For lifting a load of 50 kg through a distance of 2.5 cm, an effort of 12.5 kg is moved through a distance of 40 cm. The efficiency of the lifting machine, is
60 %
65 %
70 %
75 %
Pick up the correct statement from the following. The kinetic energy of a body
Before impact is equal to that after impact
Before impact is less than that after impact
Before impact is more than that after impact
Remain constant
A simple pendulum of length 1 has an energy E when its amplitude is A. If its amplitude is increased to 2 A, the energy becomes
E
E/2
2E
4E
Ball A of mass 250 g moving on a smooth horizontal table with a velocity of 10 m/s hits an identical stationary ball B on the table. If the impact is perfectly elastic, the velocity of the ball B just after impact would be
Zero
5 m/sec
10 m/sec
None of these
If the angular distance, 0 = 2t3 - 3t², the angular acceleration at t = 1 sec. is
1 rad/sec²
4 rad/sec²
6 rad/sec²
12 rad/sec²
A force P of 50 N and another force Q of unknown magnitude act at 90° to each other. They are balanced by a force of 130 N. The magnitude of Q is
60 N
80 N
100 N
120 N
The piston of a steam engine moves with a simple harmonic motion. The crank rotates 120 r.p.m. and the stroke length is 2 metres. The linear velocity of the piston when it is at a distance of 0.5 metre from the centre, is
5.88 m/sec
8.88 m/sec
10.88 m/sec
12.88 m/sec
A 2 m long ladder rests against a wall and makes an angle of 30° with the horizontal floor. Where will be the instantaneous center of rotation when the ladder starts slipping? (i) 1.0 in from the wall (ii) 1.732 m from the wall (iii) 1.0 m above the floor (iv) 1.732 m above the floor The correct answer is
(i) and (iii)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)
Two forces of 6 Newtons and 8 Newtons which are acting at right angles to each other, will have a resultant of
5 Newtons
8 Newtons
10 Newtons
12 Newtons
On a ladder resisting on a smooth ground and leaning against a rough vertical wall, the force of friction acts
Towards the wall at its upper end
Away from the wall at its upper end
Upwards at its upper end
Downwards at its upper end
According to Kennedy's theorem, if three bodies have plane motions, their instantaneous centres lie on
A point
A straight line
Two straight lines
A triangle
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 motion of a bicycle wheel is
Translatory
Rotary
Rotary and translatory
Curvilinear
The angles between two forces to make their resultant a minimum and a maximum respectively are
0° and 90°
180° and 90°
90° and 180°
180° and 0°
One half of a vibration of a body, is called
Period time
Oscillation
Beat
Amplitude
Minimum pull in a suspended cable with supports at two ends is equal to
Horizontal thrust
Support reactions
Resultant of horizontal thrust and support reaction
Half the weight of the cable
The shape of a suspended cable for a uniformly distributed load over it is
Circular
Parabolic
Catenary
Cubic parabola
The motion of a particle is described by the relation x = t2- 10t + 30, where x is in metres and t in seconds. The total distance travelled by the particle from t = 0 to t = 10 seconds would be
Zero
30 m
50 m
60 m
When a body moves round a fixed axis, it has
A rotary motion
A circular motion
A translatory
A rotary motion and translatory motion
A sphere and a cylinder having the same mass and radii start from rest and roll down the same inclined plane. Which body gets to the bottom first?
Sphere with greater rotational energy at bottom than cylinder
Sphere with lesser rotational energy at bottom than cylinder
Cylinder with greater rotational energy at bottom than sphere
Both reach the bottom simultaneously with equal rotational energy at bottom
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)
Principle of Transmissibility of Forces states that, when a force acts upon a body, its effect is
Maximum if it acts at the centre of gravity of the body
Different at different points on its line of
Same at every point on its line of action
Minimum if it acts at the C.G. of the body