Find the energy of a photon of frequency 6.43 x 10^14 Hz. Let 1 eV = 1.60 × 10−19 J and Planck's constant h = 4.136 × 10−15 eV ∙ s. A. 3.27 eV
B. 1.62 eV
C. 1.94 eV
D. 2.66 eV

A photocathode has a work function is 2.5 eV. It is illuminated with white light that has a continuous wavelength band from 360 nm to 700 nm. What is the stopping potential for this white light illumination? Let 1 eV = 1.60 × 10^−19 J, the mass of an electron m = 9.11 × 10^−31 kg, the speed of light c = 3.00 × 108 m/s, and Planck's constant h = 4.136 × 10^−15 eV ∙ s.
A. 1.1 V
B. 0.85 V
C. 0.94 V
D. 1.2 V
E. 1.0 V

a 2,000 calorie based diet.

this is an example of "committed" time.

committed time, as contracted time, takes need over essential and available time since it is seen as profitable work. it alludes to the time allotted to keep up a home and family. at the point when a man is commuting using committed time this individual may feel that the drive is an obligation to family, for example, strolling youngsters to class or driving a mate to work. contracted and committed time clients may feel that their commute could really compare to the commute of important or leisure time clients on the grounds that their commute is profitable work. in this manner, they might be more disposed to pick a mechanized method of movement.  

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form