A stone dropped from a baloon that was ascending at the rate of 30 ft/sec, reaches ground after 10 secs. The height of the baloon where stone was dropped was
A.1310 ft
B.2310 ft
C.3420 ft
D.4520 ft
Category: Applied Mechanics Mcqs
A satellite orbits around the earth due to
A.Celestial force
B.Gravitational force
C.Centrifugal force
D.Centripetal force
E.All of the above
A body is vibrating with simple harmonic motion of aplitude 5 cm frequency 10 vibrations per second. The maximum value of velocity in cm/s will be
A.3.14 cm/s
B.31.4 cm/s
C.314 cm/s
D.3140 cm/s
E.31400 cm/s
Our weight will be zero under all of the following conditions EXCEPT
A.When we are ascending in a lift with acceleration of 4.9 m/s2
B.When we are freely faling
C.We are orbiting in a satellite
D.We are at the centre of the earth
Which one of the following is not the law of dry friction?
A.If friction is neglected, the reactions are always normal to the surfaces on contact
B.Friction always acts to oppose the relative motion of the free body
C.If static friction is acting, the value of the friction force may vary from zero to its maximum value
D.The force of friction is always normal to the surface
E.All of the above
A stone weighing 20 N is whirling in a vertical circle at the extremity of a string 100 cm long. The tension in the string will be zero
A.at the highest position
B.at the lowest position
C.at the midway position
D.at none of the above
A wheel 8 mts in diameter coasts to rest from a speed of 800 rpm in 10 minutes. Its angular deceleration is
A.809 rad/min2
B.308/min2
C.502 rad/min2
D.683 rad/min2
The locus of instantaneous centre of a moving rigid body
A.Involute
B.Cycloid
C.Epicycloid
D.Centrode
E.Straight line
In the above problem, acceleration of crooshead at 30? phase equals
A.520 m/s2
B.640 m/s2
C.780 m/s2
D.870 m/s2
