Answer the following question given this paragraph: Electrons were the first particles with mass to be directly confirmed to have the wavelength proposed by de Broglie. Subsequently, protons, helium nuclei, neutrons, and many others have been observed to exhibit interference when they interact with objects having sizes similar to their de Broglie wavelength. The de Broglie wavelength for massless particles was well established in the 1920s for photons, and it has since been observed that all massless particles have a de Broglie wavelength = h / p. The wave nature of all particles is a universal characteristic of nature. We shall see in following sections that implications of the de Broglie wavelength include the quantization of energy in atoms and molecules, and an alteration of our basic view of nature on the microscopic scale. The next section, for example, shows that there are limits to the precision with which we may make predictions, regardless of how hard we try. There are even limits to the precision with which we may measure an object's location or energy. Making Connections: A Submicroscopic Diffraction Grating The wave nature of matter allows it to exhibit all the characteristics of other, more familiar, waves. Diffraction gratings, for example, produce diffraction patterns for light that depend on grating spacing and the wavelength of the light. This effect, as with most wave phenomena, is most pronounced when the wave interacts with objects having a size similar to its wavelength. For gratings, this is the spacing between multiple slits. ) When electrons interact with a system having a spacing similar to the electron wavelength, they show the same types of interference patterns as light does for diffraction gratings, as shown at top left in Figure 29.24. Atoms are spaced at regular intervals in a crystal as parallel planes, as shown in the bottom part of Figure 29.24. The spacings between these planes act like the openings in a diffraction grating. At certain incident angles, the paths of electrons scattering from successive planes differ by one... Q: What were the first particles with mass to be directly confirmed to have the wavelength proposed by de broglie? Choices: - negatrons - protons - ions - electrons A:
electrons
Answer the following question given this paragraph: Rhesus blood type is determined by one common antigen. A person may either have the antigen (Rh + ) or lack the antigen (Rh - ). Q: What is the common abbreviation for noting the rhesus blood type? Choices: - h2 - AB - RNA - rh A:
rh
Q: Answer the following question given this paragraph: Most protist diseases in humans are caused by protozoa. Protozoa make humans sick when they become human parasites. Q: What are most protist diseases in humans caused by? Choices: - eukaryots - lice - ticks - protozoa A:
A: protozoa
Question: Answer the following question given this paragraph: Scientists may publish articles about their research in peer-reviewed science journals. Peer review means that the work is analyzed by peers, in other words, by other scientists. The articles are published only if the other scientists are convinced that the research is accurate and honest. Q: What is the process where scientific articles are checked and analyzed by other scientists before publication? Choices: - mechanism review - embrace review - process review - peer review A:
Answer: peer review
*Question*
Answer the following question given this paragraph: Flowers are the reproductive organs of plants. Each pea plant flower has both male and female parts. The anther is part of the stamen, the male structure that produces male gametes (pollen). The stigma is part of the pistil, the female structure that produces female gametes and guides the pollen grains to them. The stigma receives the pollen grains and passes them to the ovary, which contains female gametes. Q: What female flower structure, which is part of the pistil, receives the pollen grains and passes them to the ovary? Choices: - sepal - style - ovary - stigma A:
**Answer**
stigma
(Question)
Answer the following question given this paragraph: Centripetal force is, simply, the force that causes centripetal acceleration. Objects that move in uniform circular motion all have an acceleration toward the center of the circle and therefore, they must also suffer a force toward the center of the circle. That force is the centripetal force. For orbiting satellites, such as the moon orbiting the earth or the earth orbiting the sun, the centripetal force is produced by gravity. When an Olympic hammer thrower whirls a massive ball on a chain, the centripetal force is created by the athlete and transmitted by the chain. Q: What produces the centripetal force to keep the earth orbiting the sun? Choices: - heat - motion - weight - gravity A:
(Answer)
gravity