Question

An X-ray tube emits X-rays with a wavelength of 1.0 x 10-11 m. Calculate the potential that must be applied across the X-ray tube to give each incident electron its energy, in volts.

A ) 0.6 x 105
B ) 1.2 x 105
C ) 2.4 x 105
D ) cannot be determined

Answer 1

Answer:

1.24 x 10 to the 5 ev = 124,000 ev          its B

Explanation:

E = hc/lambda = 1.24 ev-micrometer/1.0x10 to the -5 micrometers = 1.24 x 10 to the 5 ev = 124,000 ev

h = Planck's constant = 6.626 × 10 to the -34 joule·s

c = speed of light = 2.998 × 10 to the 8 m/s

lambda is the given wavelength

E is the desired photon energy

Answer 2

The potential that must be applied across the X-ray tube to give each incident electron the appropriate energy to goose X-rays with a wavelength of 1.0 x 10-11 m out of the anode cannot be determined from the given information. (D)

The energy (or wavelength) of the emitted X-rays is NOT directly determined by the energy of the incident electrons in the x-ray tube. It's determined mainly by the substance of which the anode is composed, and the electron configuration of the substance.