Q8 / 52 · KVPY 2017 (19 Nov SA) · Chemistry
$\mathrm{C}_{60}$ emerging from a source at a speed (v) has a de Broglie wavelength of $11.0 Å$. The value of $\mathrm{v}\left(\mathrm{inm} \mathrm{s}^{-1}\right.$ ) is closest to
[Planck's constant $\left.h=6.626 \times 10^{-34} \mathrm{~J} \mathrm{~s}\right]$
- Correct answerA$0.5$
- B$2.5$
- C$5.0$
- D30
Solution
$\lambda=\frac{\mathrm{h}}{\mathrm{mv}} \Rightarrow \mathrm{v}=\frac{\mathrm{h}}{\mathrm{m} \cdot \lambda}=\frac{6.62 \times 10^{-34}}{720 \times 10^{-3} \times 11 \times 10^{-10}}$
Hence, the correct answer is option: 'A'.