composition; fingerprint b.

QUESTION 22

Spectral lines can act like a __________ to help astronomers identify the chemical __________ of the electromagnetic radiation characteristics of a star.

a.composition; fingerprint

b.class; composition

c.fingerprint; structure

d.fingerprint; composition

QUESTION 23

A simple example of the Doppler effect in everyday experience is a(n)

a.tree and its leaves

b.train and its tracks.c.ambulance and its siren.

d.car and its passengers.

QUESTION 24

1. Toward the blue end of the spectrum, __________ objects emit __________ wavelengths of light.

a.cooler; shorter

b.cooler; longer

c.hotter; shorter

d.hotter; longer

QUESTION 25

1. A reflecting telescope operates by containing a(n)

a.objective lens that refracts incoming light and concentrates it at a focus behind the lens. A second lens, the eyepiece, magnifies the concentrated light so that objects appear larger.

b.objective lens that reflects incoming light and concentrates it at a focus in front of the lens.

c.curved mirror that reflects light to a focus in front of a mirror. The larger the area of the mirror, the more light the telescope can gather. A smaller mirror at the focus sends the concentrated light to an eyepiece at the back or at the side of the telescope.

d.flat mirror that refracts light to a focus in front of a mirror. The smaller the area of the mirror, the more light the telescope can gather. A smaller mirror at the focus sends the concentrated light to an eyepiece at the back or at the side of the telescope.