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
Category: Applied Mechanics Mcqs
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
The statement the resultant of the external forces applied to a body (rigid or non-rigid) composed of a system of particles is equivalent to the vector summation of the effective forces acting on all particles-is known as
A.Nowton’s law
B.Corollary to Newton’s laws of motion
C.Mohr’s principle
D.D’ Alembert’s principle
E.Principle of dynamics
Which of the following statement is false?
A.The density of milk decreases when cream is taken out of milk
B.A cyclist should move along a zig-zag path while ascending a steep hill
C.The linear velocity of bodies near the earth’s equator (due to rotation of earth) is more than the velocities of particles at the pole
D.The potential energy of a particle has the form Ep = k2x. The force acting on the particle is constant (k is a constant)
