Alpha Particles: Time for Half Circle Motion

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An alpha particle, consisting of two protons and two neutrons, is injected into a vertical magnetic field at a speed of 2.0 x 10^5 m/s. To determine the time it takes for the particle to move halfway through a complete circle, the relevant equation T = 2πM/qB is suggested, where M is the mass of the alpha particle, q is its charge, and B is the magnetic field strength of 0.113 T. The discussion emphasizes the importance of understanding the relationship between speed and magnetic force on a moving charge to find the radius of the circular path. The mass of a helium atom should be used for calculations, while the charge of the helium nucleus is also a critical factor. Understanding these principles is essential for solving the problem effectively.
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An alpha particle (the nucleus of a helium atom) consists of two protons and two neutrons. A horizontal beam of alpha particles is injected with a speed of 2.0 105 m/s into a region with a vertical magnetic field of magnitude 0.113 T.

(a) How long does it take for an alpha particle to move halfway through a complete circle?

I am trying to apply this equation:

T = 2pieM/qB

and I thought about it, do I use the speed as my q and for m, find the mass of (two protons and two neutrons) for my m?
 
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whoknows12345 said:
An alpha particle (the nucleus of a helium atom) consists of two protons and two neutrons. A horizontal beam of alpha particles is injected with a speed of 2.0 105 m/s into a region with a vertical magnetic field of magnitude 0.113 T.

(a) How long does it take for an alpha particle to move halfway through a complete circle?

I am trying to apply this equation:

T = 2pieM/qB

and I thought about it, do I use the speed as my q and for m, find the mass of (two protons and two neutrons) for my m?
Rather than trying to apply an equation why not start by telling us what physics law applies here.

The T is the period of the circular motion, m is the mass, q is the charge, and B is the magnetic field. Look up the mass of a helium atom and use that (the electrons do not add much mass). What is the charge of a helium nucleus?

AM
 
i understand that, but when do I actually use my speed given to find the answer?
 
whoknows12345 said:
i understand that, but when do I actually use my speed given to find the answer?
What is the relationship between speed and magnetic force on a moving charge? That is what you have to use. You then have to relate that to circular motion to find the radius of the circular path. That will give you the distance the particle has to move through.

AM
 
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