# Vanda

Popular questions and responses by Vanda
1. ## Physics

A special kind of light bulb emits monochromatic light of wavelength 630 nm. Electrical energy supplied to it at the rate of 60W, and the bulb is 93% efficient at converting that energy into light energy. How many photons are emitted by the bulb during its

2. ## Physics urgent!!!!

Electrons in a beam incident on a crystal at an angle of 30ͦ have kinetic energies ranging from zero to a maximum of 5500 eV. The crystal has a grating space d=0.5 Aͦ, and the reflected electrons are passed through a slit .Find the velocities of the

3. ## Physics

The seeing ability, or resolution, of radiation is determined by its wavelength. If size of an atom is of the order of 0.1 nm, how fast must an electron travel to have a wavelength small enough to “see” an atom?

4. ## Physics

a) If the work function for a certain metal is 1.8 eV, What is the stopping potential for electrons ejected from the metal when light of wavelength 400 nm shines on the metal? b) What is the maximum speed of the ejected electrons?

5. ## Physics

Light is incident on a glass-air interface from the glass side (n=1.5), and researchers want to use the evanescent field on the air side (n=1.0) to excite the molecules adhered to the surface. It is desired that the evanescent field extend a distance δ =

6. ## Physics

Electrons in a beam incident on a crystal at an angle of 30ͦ have kinetic energies ranging from zero to a maximum of 5500 eV. The crystal has a grating space d=0.5 Aͦ, and the reflected electrons are passed through a slit .Find the velocities of the

7. ## Physics

Gamma rays of photon energy 0.511 MeV are directed onto an aluminum target and are scattered in various directions by loosely bound electrons there.a) What is the wavelength of the incident gamma rays? b) What is the wavelength of the gamma rays scattered

8. ## Physics

X-radiation from a molybdenum target (0.626 A) is incident on a crystal with adjacent atomic planes spaced 4.00x10(-10) m apart. Find three smallest angles at which intensity maxima occur in the diffracted beam?

9. ## Physics

Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km.

10. ## Physics

Gamma rays of photon energy 0.511 MeV are directed onto an aluminum target and are scattered in various directions by loosely bound electrons there.a) What is the wavelength of the incident gamma rays? b) What is the wavelength of the gamma rays scattered

11. ## Physics

X-radiation from a molybdenum target (0.626 A) is incident on a crystal with adjacent atomic planes spaced 4.00x10(-10) m apart. Find three smallest angles at which intensity maxima occur in the diffracted beam?

12. ## Physics

Gamma rays of photon energy 0.511 MeV are directed onto an aluminum target and are scattered in various directions by loosely bound electrons there.a) What is the wavelength of the incident gamma rays? b) What is the wavelength of the gamma rays scattered

13. ## Physics

Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km.