(a)  Briefly explain the following terms:
(i)  emission line spectra;
(ii)   line absorption spectra.

(b) Draw a labeled diagram showing the structure of a simple type of photocell and explain its mode of operation.

(c) State two
      (i)  reasons to show that x-rays are waves;
       (ii)  uses of x-rays other than in medicine.

(d) An electron jumps from an energy level of -1.6eV to one of -1.4 eV in an atom.  Calculate the energy and wavelength of the emitted radiation. [ h = 6.6 x 10\(^{-34}\) Js; c = 3.00 x 10\(^8\) ms\(^{-1}\); eV = 1.6 x 10\(^{-19}\) J ]  

Give three observations in support of de Broglie's assumption that moving particles behave like waves

State three methods of polirizing an unpolarized light

A wire gradually stretched by loading it until it snaps.

(a) Sketch a load-extension graph for the wire

(b) Indicate on the graph the

(i) elastic limit (E);

(ii) yield point (Y);

(iii) breaking point (B).

In an electrolysis experiment, the ammeter records a steady current of 1 A. The mass of copper deposited in 30 minutes is 0.66 g. Calculate the error in the ammeter reading. [ Electrochemical equivalent of copper = 0.00033 g C\(^{-1}\)]