A 27 kg child sits in a swing supported by two chains, each 4 m long. The acceleration of gravity is 9.8 m/s 2 . If the tension in each chain at the lowest point is 159 N, find the child’s speed at the lowest point. Note: Neglect the mass of the seat. Answer in units of m/s.

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve

Chemical energy is a form of energy. a. heat b. kinetic c. potential d. electromagnetic

Asatellite component is in the shape of a cube with 10cm edges, has an evenly distributed mass of 2 kg and one bolt hole at each of four corners. if the maximum predicted random vibration environment is 10 grms, what bolt size would be a good choice for restraint? what other factors might drive bolt size besides force/stress?