8) A vernier caliper has 25 divisions on its vernier scale and is able to measure a least value of 0.5 mm on its main scale. Its least count is equal to

9) A device used to smoothen the cyclic fluctuations of speed while delivering constant output power from the engine irrespective of the varying load demand is

10) Mass 'm' is rotating with a speed of 'w' rad/sec at radius 'r' from the axis of the shaft. It is balanced by mass 'B' at radius 'b'. The shaft speed is doubled for balance. Then the value of balancing mass 'B' is

11) For a shaft speed more than the whirling speed, the phase difference between the displacement and centrifugal force is

12) In which of the following devices is an emf generated when an external force is applied on certain crystalline material ?