Question

examine the figure shown here and consider the following absorption line spectra of four stars. star w has medium strong hydrogen lines and weak ionized calcium lines. star x has medium strong hydrogen lines and medium strong helium lines. star y has weak hydrogen lines and strong ionized calcium lines. star z has weak hydrogen lines and strong ionized helium lines. list these stars in order of surface temperature from highest to lowest. the lines of each atom or molecule are strongest at a particular temperature.

Explanation:

Step1: Analyze Star Z

Star Z has strong ionized helium lines. From the graph, strong ionized - helium lines occur at high temperatures. So Star Z is hot.

Step2: Analyze Star X

Star X has medium - strong hydrogen lines and medium - strong helium lines. Referring to the graph, this corresponds to a relatively high temperature, but lower than Star Z.

Step3: Analyze Star W

Star W has medium - strong hydrogen lines and weak ionized calcium lines. According to the graph, this indicates a lower temperature compared to Star X.

Step4: Analyze Star Y

Star Y has weak hydrogen lines and strong ionized calcium lines. From the graph, this corresponds to the lowest temperature among the four stars.

Answer:

Z, X, W, Y