Search results

  1. P

    Completing nuclear reactions

    Homework Statement Complete the following nuclear reactions, assuming that the unknown quantity signified by a question mark is a single entry. Use the following table for your answers: 0 = gamma, 1 = p, 2 = alpha , 3 = n. (a) 20X43(alpha,?)21X46 (b) 4X9(?,n)6X12 Homework Equations...
  2. P

    Finding the binding energy for lithium

    Homework Statement Find the binding energy (in MeV) for lithium 3Li8 (atomic mass = 8.022486 u). Homework Equations Binding energy = (#p)(mass proton) + (#n)(mass neutron) - (mass nuclei*c^2) The Attempt at a Solution mass proton = 1.007825 mass neutron = 1.008665 Binding energy...
  3. P

    Determining the number of photons that reach the earth

    Homework Statement Light is shining perpendicularly on the surface of the earth with an intensity of 910 W/m2. Assuming all the photons in the light have the same wavelength (in vacuum) of 668 nm, determine the number of photons per second per square meter that reach the earth. Homework...
  4. P

    At what angle does the light leave the glass

    Homework Statement The drawing shows a rectangular block of glass (n = 1.52) surrounded by a liquid with n = 1.79. A ray of light is incident on the glass at point A with a 30.0° angle of incidence. At what angle does the ray leave the glass at point B...
  5. P

    What angle is subtended when using this 270-diopter objective?

    Homework Statement An anatomist is viewing heart muscle cells with a microscope that has two selectable objectives with refracting powers of 140 and 270 diopters. When she uses the 140-diopter objective, the image of a cell subtends an angle of 3.7 x 10-3 rad with the eye. What angle is...
  6. P

    Determine image distance relative to lens

    Homework Statement Two identical diverging lenses are separated by 13 cm. The focal length of each lens is -6.5 cm. An object is located 3.0 cm to the left of the lens that is on the left. Determine the final image distance relative to the lens on the right. Homework Equations 1/i + 1/o...
  7. P

    At what angle does the light leave the glass?

    Homework Statement The drawing shows a rectangular block of glass (n = 1.52) surrounded by a liquid with n = 1.60. A ray of light is incident on the glass at point A with a 30.0° angle of incidence. At what angle does the ray leave the glass at point B...
  8. P

    How do I find the height of the image?

    Homework Statement A 1.80-cm-high object is situated 19.7 cm in front of a concave mirror that has a radius of curvature of 12.2 cm. Calculate (a) the location and (b) the height of the image. Homework Equations f=1/2R 1/image distance + 1/object distance = 1/f The Attempt at a...
  9. P

    Concave mirror - finding object and image distance

    Homework Statement A concave mirror has a focal length of 27.2 cm. The distance between an object and its image is 50.2 cm. Find (a) the object and (b) the image distance assuming that the object lies beyond the center of curvature. Homework Equations f=1/2 R 1/object distance + 1/image...
  10. P

    Finding minimum angular speed

    Homework Statement The figure illustrates Michelson's setup for measuring the speed of light with the mirrors placed on Mt. San Antonio and Mt. Wilson in California, which are 35 km apart. Using a value of 3.00 x 108 m/s for the speed of light, find the minimum angular speed (in rev/s) for the...
  11. P

    RCL Circuit - Problem due at 11 PM EST tonight, have been working on it for days!

    1. Homework Statement A series RCL circuit contains only a capacitor (C = 8.46 μF), an inductor (L = 6.01 mH), and a generator (peak voltage = 77.4 V, frequency = 2.45 x 103 Hz). When t = 0 s, the instantaneous value of the voltage is zero, and it rises to a maximum one-quarter of a period...
  12. P

    2 Capacitors in Parallel

    Homework Statement Two identical capacitors are connected in parallel to an ac generator that has a frequency of 660 Hz and produces a voltage of 27 V. The current in the circuit is 0.14 A. What is the capacitance of each capacitor? Note: The ac current and voltage are rms values and power is...
  13. P

    RCL circuit containing only a capacitor, inductor, and generator

    Homework Statement A series RCL circuit contains only a capacitor (C = 8.46 μF), an inductor (L = 6.01 mH), and a generator (peak voltage = 77.4 V, frequency = 2.45 x 103 Hz). When t = 0 s, the instantaneous value of the voltage is zero, and it rises to a maximum one-quarter of a period later...
  14. P

    Question about two circular concentric coils

    Homework Statement Two circular coils are concentric and lie in the same plane. The inner coil contains 110 turns of wire, has a radius of 0.010 m, and carries a current of 5.6 A. The outer coil contains 190 turns and has a radius of 0.014 m. What must be the magnitude of the current in the...
  15. P

    Calculating net force on a charge placed at a spot

    Homework Statement Two charges, -16 and +3.4 mC, are fixed in place and separated by 4.4 m. (a) At what spot along a line through the charges is the net electric field zero? Give the distance of the spot to the positive charge in meters (m). (Hint: The spot does not necessarily lie between...
  16. P

    Spherical surface surrounding charges find flux

    A spherical surface completely surrounds a collection of charges. Find the electric flux (with its sign) through the surface if the collection consists of (a) a single +5.5 x 10-6 C charge, (b) a single -4.8 x 10-6 C charge, and (c) both of the charges in (a) and (b). Ok, so this is what I've...
  17. P

    Two wavelengths, find time between successive beats

    Two pianos each sound the same note simultaneously, but they are both out of tune. On a day when the speed of sound is 348 m/s, piano A produces a wavelength of 0.765 m, while piano B produces a wavelength of 0.772 m. How much time separates successive beats? So I know: v=348 m/s...
  18. P

    Question about sound intensity (this should be simple I think)

    A recording engineer works in a soundproofed room that is 36.6 dB quieter than the outside. If the sound intensity in the room is 2.27 x 10-10 W/m2, what is the intensity outside? I'm not sure why I can't figure this one out.. My professor confused me when he talked about this.. Do I use...
  19. P

    Need help fast with transverse wave on string!

    A transverse wave is traveling on a string. The displacement y of a particle from its equilibrium position is given by y = (0.0230 m) sin (34.6t - 2.04x). Note that the phase angle 34.6t - 2.04x is in radians, t is in seconds, and x is in meters. The linear density of the string is 1.90 x 10-2...
  20. P

    Why pizza chefs use “pizza cutters” to slice pies into sections

    Explain, using the laws of physics, why pizza chefs use “pizza cutters” to slice pies into sections, as opposed to equally sharp knives. Your answer should not simply use words, but rather should include diagrams and quantitative analysis. I'm not even sure how to begin answering this...
Top