The diving bell contains trapped air at the same pressure as the water outside. At the surface, air
pressure is 100 kPa. As the bell descends, the pressure
on it increases by 100 kPa for every 10 m of depth.

A) What is the pressure on the diver at depths of 0m,10m,20m and 30m
B) At the surface, the bell holds 6m^3 of air. If the bell is lowered to a depth of 20m, and no more air is pumped into it, what will be the volume of the trapped air? (assume no change in temperature)

Which changes of state do the labels represent? a: b: c:

Electric field of the earth. the earth has a net electric charge that causes a field at points near its surface equal to 150 n> c and directed in toward the center of the earth. (a) what magnitude and sign of charge would a 60-kg human have to acquire to overcome his or her weight by the force exerted by the earth’s electric field? (b) what would be the force of repulsion between two people each with the charge calculated in part (a) and separated by a distance of 100 m? is use of the earth’s electric field a feasible means of flight? why or why not?

Which of these is constant for all types of electromagnetic radiation in a vacuum? select one: a. wavelength b. frequency c. photon energy d. amplitude e. velocity