How do you calculate and determine atomic number, mass number, and net charge? Atomic number is the number of protons in an atom. Mass number is the number of neutrons in an atom, and net charge describes how the protons and electrons balance out. Tip: This isn't the place to ask a question because the teacher can't reply.
PCL Tear Symptoms & Diagnosis. 1  Pain. Mild to moderate pain in the knee can cause a limp, knee âgiving outâ, or difficulty walking. 2  Swelling. Within hours of the injury, knee will swell rapidly. 3  Instability. Feeling of a loose knee and not stable when standing or walking.
An injury to the PCL can cause mild to severe damage. Doctors classify PCL injuries in these groups: 1  Grade I: The PCL has a partial tear. 2  Grade II: The ligament is partially torn and is looser than in Grade I. 3  Grade III: The ligament is completely torn and the knee becomes unstable.