5. The kinetic energy of an electron is 75% of its total energy. Find the speed of the electron. X 2.904e8] C 34

The electronic structure of atoms and molecules may be investigated using photoelectron spectroscopy. An electron in a photoelectron spectrometer is accelerated from rest by a uniform electric field to a speed of 420 km s−1 in 10 µs. Determine the kinetic energy of the electron?     a. 8.0 x 10-20 N.m       b.  1.6 x 10-25 N.m       c. 3.8 x 10-25 N.m       d. 4..0 x 10-2 N.m

5. A) Explain the special relativistic expression for energy E=mc^2. B) What is the connection with the nonrelativistic expression for the kinetic energy E= 1/2mv^2? C) Discuss the generation of energy by the unclear processes of fission and fusion.

Stopping potential (V) 7.0 6.0 5.0 4.0 3.0 2.0 1.0 f(10¹5 Hz) 0 0.50 1.0 1.5 2.0 2.5 3.0 Fig. 1 The graph in Fig. 2 shows the stopping potential as a function of the frequency of the incident light falling on a metal surface. Find the work function of this metal. A. 5.169 eV. B. 3.422 eV. C. 1.089 eV. D. 0.773 eV.