65) Which condition is necessary for an object to be in equilibrium? (A) Algebraic sum of all the horizontal components of forces acting on the object should be zero (B) Algebraic sum of all the vertical components of forces acting on the object should be zero

66) What is the bending moment at end supports of a simply supported beam?

67) One of the important factors for cutting speed of a workpiece is

68) The radius of a wheel is 80 cm and the radius of the axle is 20 cm. The velocity ratio of the wheel and axle is

69) A mild steel rod of 25 mm diameter is subjected to tensile load of 1000 kg. Calculate the stress