NEET2026PhysicsChapterActual
The given figure shows the variation of de Broglie wavelength ( ) versus 1 V for two different particles accelerated from rest, where V is the accelerating potential. If the two particles are a proton and an -particle, which of the following statements is correct?
Options
- ALine A represents the -particle and Line B represents the proton.
- BLine A represents the -particle, and its slope is exactly half that of Line B.
- CLine A represents the proton, and its slope is exactly twice that of Line B.
- DLine A represents the proton and Line B represents the -particle.
Correct answer
D. Line A represents the proton and Line B represents the -particle.
Step-by-step solution
The de Broglie wavelength of a particle of mass m and charge q accelerated through a potential difference V is given by: = h 2mqV This can be rearranged as: = ( h 2mq ) 1 V The graph of versus 1 V is a straight line passing through the origin with slope S = h 2mq . For a proton, let the mass be m_p = m and charge be q_p = e . The slope is: S_p = h 2me For an -particle, the mass is m_ = 4m and charge is q_ = 2e . The slope is: S_ = h 2(4m)(2e) = h 16me = 1 2 2 h 2me = S_p 2 2 Since S_p > S_ , the line corresponding