Q1. Snoop, in hot pursuit of the Red Baron, is flying his vintage warplane in a "loop-the-loop" path. His instruments tell him that plane is level (at the bottom of the loop) and travelling at a speed of 180km/h. He is sitting on a set of bathroom scales. He notes that scales show four times his normal weight. What is the radius of the loop, in meters?
Q2. Richard, mass 75 kg, and Carmelita, who is lighter, are enjoying Lake Merced at dusk in a 35 kg canoe. When the canoe is at rest in the placid water, they exchange seats, which are 3.0 m apart and symmetrically located respecting the canoe's center. Ricardo notices that the canoe moved 45 cm relative to a submerged log throughout the exchange and calculates Carmelita's mass, which she has not told him. What is it?