Prisms and Gratings: How Light is Split into Spectra Quiz

If white light is composed of many colors, and if each color bends at a slightly different angle when entering a new material, then the colors will spread out into a rainbow; this specific spreading of light is called dispersion.

If light travels from air into a denser material like glass, then its speed decreases; if it hits the glass at an angle, then this change in speed causes the light to bend (refract).

If a prism uses refraction (bending light through a material), but a diffraction grating uses interference (bending light around edges), then they rely on different physical principles to achieve the same goal of splitting light.

If starlight passes through or reflects off a surface with microscopic parallel lines, then the light waves interfere with each other; if this interference causes the colors to separate, then the tool is a diffraction grating.

If spectroscopy requires capturing light (telescope), straightening the rays (collimator), and splitting them into colors (prism/grating), then these four are essential; if barometers measure air pressure, they are not used to study light spectra.

If violet light has a shorter wavelength than red light, then it interacts more strongly with the atoms in the glass; if it interacts more, it slows down more and therefore bends at a sharper angle than any other visible color.

If the refractive index of glass is lower for longer wavelengths, and if a lower index means light is slowed down less, then red light (long wavelength) travels through the glass at a higher speed than violet light.

If we use an optical tool to separate light into its individual wavelengths, then the resulting visual representation of those colors is defined as a spectrum.

If every element absorbs or emits specific wavelengths of light, and if we split the star's light into a spectrum, then we can see dark or bright lines that act like fingerprints to identify the chemicals inside.

If a source is solid or high-pressure gas (like a light bulb filament), then it emits light at every wavelength; if every wavelength is present, then the spectrum appears as an unbroken band of all colors.

If white light is a mixture of all visible wavelengths, and if a prism forces each wavelength to bend at a unique angle, then the mixture must physically separate into its individual colors.

If a diffraction grating uses wave interference, and if longer wavelengths (red) are spread out at wider angles than shorter wavelengths (violet), then the red light will appear further from the center of the pattern than violet light.

If we are measuring the physical size of one complete cycle of a light wave, then the standard scientific term for that distance is wavelength.

If we need to quantify how much light exists at each wavelength, and if "meter" means to measure, then a spectrometer is the specific instrument designed for this light analysis.

If the visible spectrum contains colors the human eye can see (ROYGBIV), then red, orange, yellow, and violet qualify; if infrared is invisible to the eye, it is not part of the common "visible" spectrum.

If the refractive index is a ratio of the speed of light in a vacuum to the speed in a material, and if different colors travel at different speeds, then the index defines the angle of bending for each color.

If the first prism splits white light into colors, and if the second prism is oriented to reverse that bending, then the colors will merge back together; if they merge, they return to the original state of white light.

If light enters from all directions, the resulting spectra will overlap and become blurry; if we limit the entry point to a narrow line (slit), then the resulting spectrum will be sharp and detailed.

If a grating can spread light more effectively and can be made as a mirror (avoiding glass absorption), then it is more useful for advanced research; however, high-precision gratings can actually be very expensive.

If a gas is thin and hot, its atoms are excited and release energy at very specific wavelengths; if we see these specific colors as lines without the rest of the rainbow, then we are looking at an emission spectrum.