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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.
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.
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?
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.
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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