Find the zero of foly 2x² - 12-5x and verify its relation beetween Zero and its cofficents
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172. An Electro magnetic radiation of wavelength 242 nm is just sufficient to ionise a sodium atom. Calculate the ionisation energy of sodium in kJ/mol ? 1) 494.5 2) 594.5 3) 694.5 4) 794.5 173. When a metal is irradiated with light of frequency 4.0 x 1016 s-1 the photo electrons emitted had six times the K.E as the K.E of photo electron emitted when the metal was irradiated with light of frequency 2.0 x 1016s -1 . The calculate the critical frequency of the metal 1) 2.0 x 1016 s-1 2) 1.6 x 1016 s-1 3) 3.0 x 1016 s-1 4) 4.2 x 1016 s-1 174. In photo electric effect, if the energy required to over come the attractive forces on the electron (work function) of Li, Na and Rb are 2.41eV, 2.3 eV and 2.09eV respectively, the work function of “K” could approximately be in eV 1) 2.52 2) 2.2 3) 2.35 4) 2.01 175. In photoelectric effect, the energy of the photon striking a metallic surface is 5.6 x 10-19 J. The kinetic energy of the ejected electrons is 12.0 x 10-20 J. The work function is 1) 6.4 x 10-19 J 2) 6.8 x 10-19 J 3) 4.4 x 10-19 J 4) 6.4 x 10-20 J 176. An Electro magnetic radiation of wavelength 484nm is just sufficient ionise a sodium atom. Calculate the ionisation energy of sodium in kJ/mol approximately ? 1) 494.5 2) 246.9 3) 989.0 4) 794.5 177. Suppose 10-17 J of energy is needed by the interior of human eye to see an object. How many photons of green light 550nm are needed to generate this minimum amount of energy ? 1) 14 2) 28 3) 39 4) 42 178. The ratio of the energies of two different radiations whose frequencies are 3 x 1014 Hz and 5 x 1014 Hz is 1) 3 : 5 2) 5 : 3 3) 3 : 1 4) 5 : 1 179. Which one of the following frequency of radiation (in Hz) has a wavelength of 600nm 1) 2 x 1013 2) 5 x 1016 3) 2 x 1014 4) 5 x 1014 180. What is the energy of photons that corresponds to a wave number of 5 x 10-5 m-1 1) 99.384 x 10-30 J 2) 993.84 x 10-30 J 3) 9.9384 x 10-30 J 4) 0.99384 x 10-30 J the correct address is the same time so much I really good at making me food he was in a meeting with my group members and we