Q. The maximum efficiency of a lifting machine is

View solution

Q. A machine having an efficiency less than 50%, is known as

View solution

Q. The total momentum of a system of masses (i. e. moving bodies) in any one direction remains constant, unless acted upon by an external force in that direction. This statement is called

View solution

Q. The velocity ratio of a differential pulley block with D and d as the diameters of larger and smaller pulley, is

View solution

Q. The unit of mass moment of inertia in S.I. units is kg-m².

View solution

Q. The moment of inertia of a solid cylinder of mass m, radius r and length l about the longitudinal axis or polar axis is

View solution

Q. In a screw jack, the effort required to lift the load is given by(where W = Load lifted, α = Helix angle, and φ = Angle of friction.)

View solution

Q. The terms 'leverage' and 'mechanical advantage' Of a compound lever have got the same meaning.

View solution

Q. A couple produces

View solution

Q. Energy may be defined as the capacity of doing work.

View solution

Q. An irregular body may have more than one centre of gravity.

View solution

Q. The rate of doing work is known as

View solution

Q. In a wormed geared pulley block, if the number of teeth on the worm wheel is doubled, then its velocity ratio is also doubled.

View solution

Q. Moment of inertia of a circular section about its diameter (d) is

View solution

Q. The radius of gyration is the distance where the whole mass (or area) of a body is assumed to be concentrated.

View solution

Q. If three coplaner forces acting on a point are in equilibrium, then each force is proportional to the sine, of the angle between the other two.

View solution

Q. A rubber ball is dropped from a height of 2 m. If there is no loss of velocity after rebounding, the ball will rise to a height of

View solution

Q. When the spring of a watch is wound, it will possess

View solution

Q. For a self locking machine, the efficiency must be

View solution

Q. The resultant of the two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P. Then

View solution