A chest x-ray uses 10 keV photons. A 60 kg person receives a 30 mrem dose from one x-ray that exposes 25% of the patient’s body. How many x-ray photons are absorbed in the patient’s body?
What is the activity in and in of a 2.0 mg sample of ?
The first three energy levels of the fictitious element X are shown in Figure P29.56. Hint: The energy of the photon is not the energy transferred to the atom in the collision. Part A What wavelengths are observed in the absorption spectrum of element X? Give your answers in nm. Part B State whether each of your FIGURE P29.56 wavelengths in […]
If the nucleus is a few fm in diameter, the distance between the centers of two protons must be = 2 fm. Part A Calculate the repulsive electric force between two protons that are 2.0 fm apart. Part B Calculate the attractive gravitational force between two protons that are 2.0 fm apart. Could gravity be the force […]
What is the length of a box in which the difference between an electron’s first and second allowed energies is 1.0 x 10^-19 J?
Exposure to a sufficient quantity of ultraviolet light will redden the skin, producing erythema sunburn. The amount of exposure necessary to produce this reddening depends on the wavelength. For a 1.0 cm^2 patch of skin, 3.7 mJ of ultraviolet light at a wavelength of 254 nm will produce reddening; at 300 nm wavelength, 13 mJ are required. a. What is the […]
Light of constant intensity but varying wavelength was used to illuminate the cathode in a photoelectric-e ffect experiment. The graph of Figure P28.54 shows how the stopping potential depended on the frequency of the light. What is the work function, in eV, of the cathode?
Unpolarized light passes through a vertical polarizing filter, emerging with an intensity I0. The light then passes through a horizontal filter, which blocks all of the light; the intensity transmitted through the pair of filters is zero. Suppose a third polarizer with axis 45° from vertical is inserted between the first two. What is the transmitted intensity now?
Once dark adapted, the pupil of your eye is approximately 7 mm in diameter. The headlights of an oncoming car are 120 cm apart. If the lens of your eye is limited only by diffraction, at what distance are the two headlights marginally resolved? Assume the light’s wavelength in air is 600 nm and the index of refraction inside […]
A spy satellite uses a telescope with a 2.0-m-diameter mirror. It orbits the eaJth at a height of 220 km. What minimum spacing must the re be between two objects on the earth’s surface if they are to be resolved as distinct objects by this telescope? Assume the telescope’s resolution is limited only by diffraction and that it is recording […]