(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A uniform magnetic field of magnitude 0.137 T is directed along the positive x axis. A positron moving at a speed of 5.40 106 m/s enters the field along a direction that makes an angle of θ = 85.0° with the x axis (see figure below). The motion of the particle is expected to be a helix.

(a) Calculate the pitch p of the trajectory as defined in figure.

(b) Calculate the radius r of the trajectory as defined in figure.

2. Relevant equations

vx = sqrt(vy^2 + vz^2)

R = (m (vx) )/ qB

T = (2 pi r ) / vx

3. The attempt at a solution

To find vx multiply v vector by sin(5 degrees). Plugging in values to radius. Answer is significantly wrong. To find pitch, p = (vx)T = 2 pi r.

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# Homework Help: Positron Helix magnetic field, find pitch and radius

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