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

Air conditioners not only cool air, but dry it as well. suppose that a room in a home measures 5.0m×9.0m×2.4m . if the outdoor temperature is 30 ∘c and the vapor pressure of water in the air is 85 % of the vapor pressure of water at this temperature, what mass of water must be removed from the air each time the volume of air in the room is cycled through the air conditioner? the vapor pressure for water at 30 ∘c is 31.8 torr.

Ben (55kg) is standing on very slippery ice when junior (25kg) bumps into him. junior was moving at a speed of 8 m/s before the collision and ben and junior embrace after the collision. find the speed of ben and junior as they move across the ice after the collision. give the answer in m/s. describe the work you did to get the answer.

Ineed this now one scientist feels that the changes in global climatic patterns may be good for the health of the biosphere. another scientist feels that sharp changes in climatic patterns could result in the extinction of the biosphere. which of these is the most likely reason the two scientists gave conflicting opinions on the impact of changes in the global climatic pattern? they do not have enough knowledge on the topic. they did not discuss the issue among themselves. they believe conflicting opinion strengthens science. they study different areas of science and have different scientific focuses.