Engineering mechanics


The velocity ratio of a differential wheel and axle with D as the diameter of effort wheel and d1,and d2 as the diameters of larger and smaller axles respectively, is

A. `(D)/(d_1 + d_2)`
B. `(D)/(d_1 - d_2)`
C. `(2D)/(d_1 + d_2)`
D. `(2D)/(d_1 - d_2)`


When a body of mass moment of inertia I (about a given axis) is rotated about that axis with an angular velocity to, then the kinetic energy of rotation is

A. `l omega`
B. `lomega^2`
C. `0.5 l omega`
D. `0,5 l omega^2`


If a number of forces are acting at a point, their resultant is given by

A. `(Sigma V)^2 +(Sigma H)^2`
B. `sqrt((Sigma V)^2 +(Sigma H)^2)`
C. `(Sigma V)^2 + (Sigma H)^2 + 2(Sigma V)(Sigma H)`
D. `sqrt((Sigma V)^2 + (Sigma H)^2 + 2(Sigma V)(Sigma H))`


The cartesian equation of trajectory is(where u = Velocity of projection, `alpha` = Angle of projection, and x, y = Co-ordinates of any point on the trajectory after t seconds.)

A. `y = (gx^2)/(2u^2 cos 2 alpha) + x tan alpha`
B. `y = (gx^2)/(2u^2 cos 2 alpha) - x tan alpha`
C. `y = x tan alpha - (gx^2)/(2u^2 cos alpha)`
D. `y = x tan alpha + (gx^2)/(2u^2 cos alpha)`


A number of forces acting at a point will be in equilibrium, if

A. all the forces are equally inclined
B. sum of all the forces is zero
C. sumof resolved parts in the vertical direction is zero (i.e. `Sigma`V = 0)D.
D. none of these