Before entering a mass spectrometer, ions pass through a velocity selector consi

Question

Before entering a mass spectrometer, ions pass through a velocity selector consisting of parallel plates separated by 2.2 mm and having a potential difference of 186 V. The magnetic field between the plates is 0.42 T. The magnetic field in the mass spectrometer is 1.2 T. (a) Find the speed of the ions entering the mass spectrometer. m/s You currently have 1 submissions for this question. Only 10 submission are allowed. You can make 9 more submissions for this question. (b) Find the difference in the diameters of the orbits of singly ionized^238 U and^235 U. (The mass of a^235 U ion is 3.903 times 10^-25 kg.) mm You currently have 0 submissions for this question. Only 10 submission are allowed. You can make 10 more submissions for this question.

Explanation / Answer

for a charged particle in a magnetic field,

balancing magnetic force with centripetal force:

m*v^2/r=q*v*B

where m=mass

v=speed

r=radius

q=charge

B=magnetic field

then r=m*v/(q*B)

diameter=2*r=2*m*v/(q*B)

as speed of both particles , as well as charge remains the same,

difference in diameter=difference in mass*(2*v/(q*B))

mass of 238 U=(3.903*10^(-25)/235)*238

so mass difference=(238-235)*3.903*10^(-25)/235

=3*3.903*10^(-25)/235 kg

so difference in diamter=(3*3.903*10^(-25)/235)*(2*201298.7/(1.6*10^(-19)*1.2))

=0.0104477 m

=10.4477 mm

Related Questions

Navigate

• Browse (All)
• Browse B
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.