Understanding Rydberg's Constant: What Do R(sub)H and R(sub)infinity Represent?

[Astronomer1]

1. Rydberg's Constant: what's the difference between R (sub) infinity & R (sub) H?



2. R (sub) H = -2.1799x10^-18 J | R (sub) infinity = 1.0974x10^7 1/m (m = meters)



3. No attempt to solve the Q yet; I don't know what's the difference between the two? What do these 2 stand for?

 

[Simon Bridge]

This is a question about the definitions of symbols - have you tried looking them up?