In a particle diffraction experiment, a beam of ionized atoms of mass 4.0 × 10-27 kg is accelerated to a speed of 6.0 × 105 m s-1.
To produce a diffraction pattern with the same fringe spacing using a different beam of particles, the new particles must have the same de Broglie wavelength.
The table below lists the mass and speed of four alternative beams of particles, A, B, C, and D.
| Particle beam | Mass / kg\text{kg}kg | Speed / m s−1\text{m s}^{-1}m s−1 |
|---|---|---|
| A | 1.6 × 10-27 | 1.5 × 106 |
| B | 1.0 × 10-27 | 1.2 × 106 |
| C | 1.6 × 10-27 | 2.4 × 105 |
| D | 2.0 × 10-27 | 3.0 × 105 |
Which particle beam will produce the same diffraction pattern?
A
B
C
D
26 exam-style questions on OCR A A Level Physics Quantum physics, covering Photons, The photoelectric effect, and Wave–particle duality. Each one has a worked solution and a mark scheme showing where the marks go.