Most respondent candidates were able to state the properties of cathode rays but could not state how the intensity and energy of cathode rays may be increase. Performance was fair.
The expected answers are:
(a) Properties of cathode rays
e.g Cathode rays
- are negatively charged
- travel in straight line (in field free space)
- are deflected by electric / magnetic field
- possess (kinetic) energy
- possess momentum
- can produce intense heat
- affect photographic films.
(b)(i) The intensity of cathode rays may be increased by raising the voltage across the
heater/the temperature of the cathode/increasing the current.
(ii) The energy of cathode rays may be increased by increasing the potential
difference between the anode and the cathode/the anode potential.