1. A beam of particles, all with the same momentum but with a variety of masses and charges, enters a region of uniform magnetic field, as shown in the picture. Slits are placed at the end of the field region such that only particles traveling along a circle of specific radius ρ are allowed to pass through.
A) What quantity (mass, charge, or velocity) does this device select for?
B) What is the value of the selected quantity?

2. mass
b) charge
c) velocity

3. 𝑚𝑣 𝜌B
𝑞𝜌𝐵
𝑞𝐵𝜌 𝑚 𝐵ρ
e) 𝑚𝑣
Note:
Momentum p = mv