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Hello all,

Earlier today I had an electromagnetism exam, and it seems to me that this problem is unsolvable.

There's just too little information given.

So let's say that, because it's initial speed is perpendicular, the force acting on the proton equals:

F = qvB

q = charge

v = speed

B = magnetic field strength

This force is the centripetal force:

qvB = pv/r

p = momentum (mv)

r = radius circle

So.. Let's solve for r.

r = p/qB

But that doesn't help much.

See: you don't know how long the proton is present in the magnetic field. You could calculate the circumference of a circle with radius

Anyway, my girlfriend is convinced this is solvable. Am I overlooking something?

Hello all,

Earlier today I had an electromagnetism exam, and it seems to me that this problem is unsolvable.

There's just too little information given.

*A proton enters an uniform magnetic field. It's initial speed v is perpendicular to the magnetic field.*

The strength of the magnetic field is B. You also know the direction of the magnetic field (see: https://imgur.com/a/HSTT7Qh).

Calculate the total distance the proton travels.The strength of the magnetic field is B. You also know the direction of the magnetic field (see: https://imgur.com/a/HSTT7Qh).

Calculate the total distance the proton travels.

So let's say that, because it's initial speed is perpendicular, the force acting on the proton equals:

F = qvB

q = charge

v = speed

B = magnetic field strength

This force is the centripetal force:

qvB = pv/r

p = momentum (mv)

r = radius circle

So.. Let's solve for r.

r = p/qB

But that doesn't help much.

See: you don't know how long the proton is present in the magnetic field. You could calculate the circumference of a circle with radius

*r*, you could calculate the time it takes the proton to travel 2πr but you still wouldn't be able to calculate the total distance travelled without a given time.Anyway, my girlfriend is convinced this is solvable. Am I overlooking something?

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