1. The source of the sun's energy is a process called nuclear fusion. In this process, protons collide and create larger particles. As a result, huge amounts of energy are liberated. The problem, however, is that for fusion to occur, the protons have to "collide"-that is, they have to pass near to each other–say, within a proton diameter, 10-15 m. The question now arises, Are protons inside the sun actually moving that fast? b) Calculate how high the temperature would have to be inside the sun, in order for the speed you found in part (a) to be a typical rms speed for particles in an ideal gas. c) The actual temperature in the solar interior is about 107 K. Is this consistent with the fusion mechanism? • a) Suppose that one proton is fixed in place. If another proton starts out from very far away, then how fast must it be going initially, if it is to approach to within 10-15 m of the fixed proton?

1. The source of the sun's energy is a process called nuclear fusion. In this process, protons collide and create larger particles. As a result, huge amounts of energy are liberated. The problem, however, is that for fusion to occur, the protons have to "collide"-that is, they have to pass near to each other–say, within a proton diameter, 10-15 m. The question now arises, Are protons inside the sun actually moving that fast? b) Calculate how high the temperature would have to be inside the sun, in order for the speed you found in part (a) to be a typical rms speed for particles in an ideal gas. c) The actual temperature in the solar interior is about 107 K. Is this consistent with the fusion mechanism? • a) Suppose that one proton is fixed in place. If another proton starts out from very far away, then how fast must it be going initially, if it is to approach to within 10-15 m of the fixed proton?