What is the best head rope?

Please Help! I use a rope 2.00 m long to swing a 10.0-kg weight around my head. The tension in the rope is?

• I use a rope 2.00 m long to swing a 10.0-kg weight around my head. The tension in the rope is 20.0 N. In half a revolution how much work is done by the rope on the weight? Please show all the work and steps

• Answer:

  None. Work is the scalar or dot product of the Force vector and the Displacement vector. The force is directed radially toward the center of rotation, the displacement is tangential and normal to the direction of the force. Since there is no component of force in the direction of movement, the scalar product of the vectors is zero and there is no work done on the swinging weight. In a conservative system, the work done on an object equates to a change in the total energy of the object. In this case, neither kinetic nor potential energy of the weight changes so there is no work done on the object.