A model of a helicopter rotor has four blades, each of length 3.50 m from the central shaft to the blade tip. The model is rotated in a wind tunnel at a rotational speed of 540 rev/min a) What is the linear speed of the blade tip?(b) What is the radial acceleration of the blade tip expressed as a multiple of g?

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