Question

1 Two wires hold up a massive beam of length L=16 m and mass 330 kg. A box of mass 220 kg hangs from a wire that hangs from the beam a distance x=12 m away from the left edge of the beam. What is the tension in RIGHT support wire?

2. The work completed in accelerating a flywheel from rest to the angular speed of 18.5 revolutions per second is 17.5 kJ. What is the moment of inertia of flywheel?

3. A large tree trunks are floating in the sea. The density of the sea water is 1025 kg/m3, density of the trunk is 650 kg/m3. What fraction of the trunk's volume is above the surface of water?

4. Through a bad weather day with an atmospheric pressure of 0.9 atm a submarine dives at a depth of 11.3 m. The inside of the submarine is held at a pressure of 1.2 atm. What is the least force needed for someone inside submarine to push open the circular escape hatch with a diameter of 0.8 m in an emergency? (The hatch is placed on the side of the submarine - suppose the hatch is at the nominal diving depth, density of water is 1000 kg/m^3)