Calendar: 1852-1853 Page 343

APPLIED SCIENCES 339 Find the resultant of the parallel forces and as in the figure Show how to find the ten- sion on the tie-beam in the sim- plest form of roof What is the centre of gravity Find it in the case of flat board in the shape of triangle State the principle of the equality of moments and show how to determine the centre of gravity of given set of bodies by means of it Example Find the centre of gravity of the figure Β CD in which Ζ ADC 90 AD 10 DC BC also AD and BC are parallel Explain the meaning of the term work and how it is estimated when the motion is neither rectilineal nor in the direction of the force Explain the mechanical effect of the wedge by the principle of work Show how to take into account the frictions of the pivots or bearings in the case of the wheel and axle and calculate the modulus supposing that radius of wheel 10 radius of axle radius of pivot coefficient of friction 10 State the Three Laws of Motion VI -draining Make drawing of geometrical diagrams of six distinctprinciples onwhich the alternate rectilinear motion of the piston is converted into alternate circular motion of the beam in steam-engines