Aboat is traveling upstream in the positive direction of the x axis at 10 km/h with respect to the water of a river. the water is flowing at 7 km/h with respect to the ground. (a) what is the velocity of the boat with respect to the ground?

11 words used to describe an object are called itsor characteristics.total12 is the amount of matter in an object.helt udedelerde elettroduodet littletadli dituntut uploaded13 the metric unit used to measure weight is them.14 if a toy has a mass of 1 kg, it has an earth weight 15 the density of liquid water isti

Groups of organs that work together to complete a process in the body are called: a. cells b. tissues c. nerves d. systems

Some material consisting of a collection of microscopic objects is kept at a high temperature. a photon detector capable of detecting photon energies from infrared through ultraviolet observes photons emitted with energies of 0.3 ev, 0.5 ev, 0.8 ev, 2.0ev, 2.5ev, and 2.8ev. these are the only photon energies observed. (a) draw and label a possible energy-level diagram for one of the microscopic objects, which has four bound states. on the diagram, indicate the transitions corresponding to the emitted photons. explain briefly. (b) would a spring–mass model be a good model for these microscopic objects? why or why not? (c) the material is now cooled down to a very low temperature, and the photon detector stops detecting photon emissions. next, a beam of light with a continuous range of energies from infrared through ultraviolet shines on the material, and the photon detector observes the beam of light after it passes through the material. what photon energies in this beam of light are observed to be significantly reduced in intensity (“dark absorption lines”)? explain briefly.