Question

ultraviolet light wavelenght 300nm strikes a

L P spher SMP 12) In the experiment shown below, a pulse of ultraviolet lightwavelength 300 nm) strikes a small sphere of aluminum at t=0. The work function of Al is 4.100 eV. a). What is the minimum time for electrons to show up at the collecting ball that is 1 cm away? b). Now the wavelength of the incident light is decreased to 200 nm and a current is measured. What happens to the current if the power of the light source is then doubled (i.e. twice as much intensity on the sphere)?

Answer 1

@ = 3000m= 3x10 tym, wa ulev = 48 x1681079 ye E = he 6-6x10 34 x 3x10 - 6.6x10-19 juli 3x107 Einstein photo elechic ean kof of elected e = E-Wo = (6.6 6.5681019 me 62 = + 0. 04 X10 19 162 = 0.08x102 -- 0.0087.91 x102 9.1810-31 o = 0.09376x16 = 9.376x107 mise = 9:376x102= fa f 1.0666x10 t = 0.107 MSc 21cm=16 6 Power = Current) 2 x Resistance P = I2R - & p ho ar lime - eano e B = 9P I²R = 2X IR I 272 TI - SP Jos