The statement --- if forces acting on a point can be represented in magnitude and direction by the sides of a polygon taken in order then their resultant will be represented in magnitude and direction by the closing side of the polygon taken in opposite order ---- is known as
An electric motor drives a windless which hauls up a crate A of weight W = 500 kg up an inclined plane through a height of 10 m in 2 minutes. The torque acting on the windless is 25 kgm and the drum of the windless makes 30 rpm. The efficiency of the inclined plane would be
A ball of mass 1 kg moving with a velocity of 2 m/sec collides directly with a stationary ball of mass 2 kg. If the first ball comes to rest after the impact the velocity of second ball after impact will be
A flywheel weighs 400 kg and has a radius of gyration of 30 cm about its axis of rotation. It is mounted on a shaft subjected to a moment of 40 kgm. If the flywheel starts from restits speed after 3 seconds wil be
A rigid body is suspended vertically at a point and oscillates with a small amplitude under the action of the force of gravity. Such an arrangement is called
A locomotive of weight 100 tonnes is attached to train of wagons weighing 1000 tonnes. The locomotive pulls the wagons with a constant velocity of 36 km/hour. When the coupling between the train and wagons breaks, the wagons roll on 95 m in 10 sec. The distance between the locomotive and the wagons at this instant assuming that the forces acting on the train are unaltered would be
