Two children stretch a jump rope between them and send wave pulses back and forth on it. the rope is 4.5 m long, its mass is 0.42 kg, and the force exerted on it by the children is 71 n. (a) what is the linear mass density of the rope (in kg/m)?
(b) what is the speed of the waves on the rope (in m/s)?

Suppose a force of 60 n is required to stretch and hold a spring 0.1 m from its equilibrium position. a. assuming the spring obeys hooke's law, find the spring constant k. b. how much work is required to compress the spring 0.5 m from its equilibrium position? c. how much work is required to stretch the spring 0.6 m from its equilibrium position? d. how much additional work is required to stretch the spring 0.1 m if it has already been stretched 0.1 m from its equilibrium? a. kequals 600