The electric current in an X-ray tube (from the target to the filament) operating at 40 kV is 10 mA. Assume that on an average, 1% of the total kinetic energy of the electrons hitting the target are converted into X-rays.
(a) What is the total power emitted as X-rays and
(b) how much heat is produced in the target every second?
Given:
operating voltage= 40Kv
current = 10mA
1% of total kinetic energy gives X-rays
n=0.625×1017 (number of electrons)
K.E of one electron=eV
=1.6×10-19×40×103
=6.4×10-15 joules
Tke= 0.625×6.4×1017×10-15
Tke= 4×102 joules
b) Heat produced in the target per second
=400-4=396 Joules of heat
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