Calculate the value of the force shown by the dynamometer, when it is known that the rod is in equilibrium. Point O axis of rotation

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 10.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.90 m/s; (b) he is then lifted at the constant speed of 4.90 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 68.0 kg rescue by the force lifting him during each stage?

Atomic nuclei of almost all elements consist of

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.