# Protons with a momentum of 4.8X10^-20 kgm/s are forced into a clockwise circular path with a 75m radius in a particle accelerator. Calculate the magnitude of the magnetic field surrounding the...

Protons with a momentum of 4.8X10^-20 kgm/s are forced into a clockwise circular path with a 75m radius in a particle accelerator. Calculate the magnitude of the magnetic field surrounding the protons.

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### 1 Answer

You need to use the following equation to find the magnitude of magnetic field, such that:

`F_B = F_C` (magnetic force `F_B` = centripetal force `F_C` )

`q*v*B = (m*v^2)/r` => `B = (m*v^2)/(r*q*v)`

Reducing duplicate factors, yields:

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

The problem provides the momentum of `4.8*10^(-20)` , hence, you may replace the value for m*v, such that:

`B = (4.8*10^(-20))/(1.6*10^(-19)*75)`

`B = 0.04*10^(-1) => B = 0.004T`

**Hence, evaluating the magnitude of the magnetic field, under the given conditions, yields **`B = 0.004T.`