(a)(i) What is meant by the term artificial radioactivity?

(ii) Complete the table below

Emission	Nature	Charge	Ionizing
	High speed electron		Moderately ionizing
		Neutral	Negligible ionizing ability
Alpha particles		Positive

 

(b) In an x-ray tube, an electron is accelerated from rest towards a metal target by a 30 kV source. Calculate the kinetic energy of the electron. [e=1.6 x 10\(^{-19}\)C]

(c) The table below shows the frequencies of radiations incident on a certain metal and the corresponding kinetic energies of the photoelectrons.

Frequency x 10\(^{14}\)(Hz)	6.8	8.0	9.2	10.0	11.0
Kinetic energy x 10\(^{-19}\)(j)	0.8	1.6	2.4	2.9	3.8

 

(i) Plot a graph of kinetic energy, K.E, on the vertical axis and frequency, f, on the horizontal axis starting both axes from the origin (0,0).

(ii) From the graph, determine the:

i. Planck's constant;

ii. Threshold frequency of radiations;

iii. Work function of the metal.