A student graduating from a Baltimore City high school throws their cap in the air at the end of the commencement ceremony. The cap leaves the student's hand at a speed of 98 m/s. How
long did the cap take to reach its' highest point? How long did it stay in the air? How high did
the cap travel into the air? There are three questions to answer, and you must show your work
to get all three points.

Consider an insulating crystal, made up of layers of atoms. what form would you expect the temperature dependence of the phonon heat capacity to approach at extremely low temperatures if the interlayer coupling is i)very strong (rigid coupling), and ii) very weak. explain.

An electromagnet is a device in which moving electric chargers in a coil of wire create a magnet. whats one advantage of using electromagnetic in devices

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light