A beam of light consists of five wavelengths 4000∘A,4800∘A,6000∘A,7000∘A and 7800∘A. The light beam is falling normally over a metal surface of area 10−4 m2 with a work function of 1.9 eV. Intensity of light beam is 7.5×10−3 W/m−2, which is equally divided among the constituent wavelengths. If there is no loss of light energy, number of photoelectrons emitted per second is

A beam of light consists of five wavelengths 4000∘A,4800∘A,6000∘

1.	A beam of light consists of five wavelengths 4000∘A,4800∘A,6000∘A,7000∘A and 7800∘A. The light beam is falling normally over a metal surface of area 10−4 m2 with a work function of 1.9 eV. Intensity of light beam is 7.5×10−3 W/m−2, which is equally divided among the constituent wavelengths. If there is no loss of light energy, number of photoelectrons emitted per second is
Answer» A beam of light consists of five wavelengths $4000 \circ A, 4800 \circ A, 6000 \circ A, 7000 \circ A a n d 7800 \circ A$ . The light beam is falling normally over a metal surface of area $10^{- 4} m^{2}$ with a work function of 1.9 eV. Intensity of light beam is $7.5 \times 10^{- 3} W / m^{- 2}$ , which is equally divided among the constituent wavelengths. If there is no loss of light energy, number of photoelectrons emitted per second is

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