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Contemporay Astonomy

I have given my response to the following chapter quiz questions (see attachment). Please correct and provide the correct answers if/when mine are incorrect.

1.Which of the following lists of different types of electromagnetic radiation is correctly ordered in wavelength, from shortest to longest?

A) Gamma rays, ultraviolet, radio, infrared.

B) Radio, ultraviolet, infrared, gamma rays.

C) Radio, infrared, ultraviolet, gamma rays.

D) Gamma rays, ultraviolet, infrared, radio.

2. What is the relationship between color and wavelength for light?

A) Wavelength increases from violet to yellow-green, then decreases again to red.

B) Wavelength decreases from violet to red.

C) Wavelength increases from violet to red.

D) Wavelength depends only on brightness and is independent of color.

3. The temperature scale most often used by scientists is the

A) Kelvin scale.

B) Richter scale.

C) Fahrenheit scale.

D) Celsius scale.

4. A blackbody is an idealized object in physics and astronomy that

A) reflects no light, and emits light in a manner determined by its temperature.

B) reflects and emits radiation in a manner that is completely determined by its temperature.

C) reflects and emits light with the same intensity at all wavelengths.

D) does not emit or reflect any radiation.

5. The star Vega has a higher surface temperature than the Sun. If so, then, with IR referring to infrared and UV referring to ultraviolet,

A) Vega emits less IR and more UV flux than the Sun.

B) Vega emits more IR and more UV flux than the Sun.

C) Vega emits more IR and less UV flux than the Sun.

D) Vega emits less IR and less UV flux than the Sun.

6. Wien's law, relating the peak wavelength lmax of light emitted by a dense object to its temperature T, can be represented by

A)lmax = constant ยด T4.

B)lmaxT = constant.

C)lmax = constant/T2.

D)lmax/T = constant.

7. What is a diffraction grating?

A) A flat, rectangular array of closely spaced photosensitive cells.

B) A piece of glass with thousands of closely spaced, parallel grooves.

C) An array of many radio telescopes used to observe a single source simultaneously.

D) A triangular prism of solid glass, used to disperse light into its colors.

8. An atom consists of

A) negatively charged electrons moving around a very small but massive, positively charged nucleus.

B) neutrons orbiting an electrically neutral nucleus composed of protons and electrons.

C) positive protons, neutral neutrons, and negative electrons, orbiting a small but massive black hole.

D) negatively charged electrons and positively charged protons, mixed uniformly throughout the volume of the atom.

9. The Balmer series of visible spectral emissions from hydrogen gas arises from transitions in which electrons jump between energy levels

A) from all levels to the ground state, n = 1.

B) from higher levels to the second excited level, n = 3.

C) between adjacent levels (e.g., n = 2 to n = 1, n = 3 to n = 2, n = 4 to n = 3, etc.).

D) from higher levels to the first excited level, n = 2.

10. The Doppler effect is the change in the wavelength of light caused by the source

A) being within a high gravitational field.

B) being embedded in a cloud of dust and gas.

C) being in an intense magnetic field.

D) moving with respect to the observer.

Thanks.

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