JEE Advanced2007PhysicsElectromagnetic WavesActual
Statement I If the accelerating potential in an X-ray tube is increased, the wavelengths of the characteristic X -rays do not change. Statement II When an electron beam strikes the target in an X-ray tube, part of the kinetic energy is converted into X-ray energy.
Options
- AStatement I is true, Statement II is true; Statement II is a correct explanation for Statement I
- BStatement I is true, Statement II is true; Statement II is NOT a correct explanation for Statement I
- CStatement I is true, Statement II is false
- DStatement I is false, Statement II is true
Correct answer
B. Statement I is true, Statement II is true; Statement II is NOT a correct explanation for Statement I
Step-by-step solution
Cut-off wavelength depends on the accelerating voltage, not the characteristic X -rays. Further approximately 2 % kinetic energy of the electrons is utilised in producing X-rays. Rest 98 % is lost in heat. Option (b) is correct.