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ok so 1- the magnetic momentum is = to u in the k axis ( xyz - ijk )

and the magnetic field B = -A/z4 + Be^Cz) , also in the k axis orientation

so the magnetic force F , that is applied on the magnetic momentum is given by

4 choices ; and as i can understnd it, 3 of them are the derivatives (2 bad ones ) of the b field and the other looks like the primitive of b . all 4 choice have u multiplied by it .

a- f = ( 4uA/z^5 + uBe^Cz) in k orientation

b- ( - 4uA/z^5 + uBCe^Cz) in k orientation

c- (3uA/z^3 + uBCe^Cz) in k orientation

d- (4uA/z^5 + uBCe^Cz) in k orientation

pretty sure the answer is D ,altough at first i thought it was b

as D is the correct derivtive of the b field, and its terms multiplied by the momentum value. So the magnetic momentum feels a force made by itself ?

again with a magnetic momentum of u = 1 (i) + 2 (k) , surrounded by a magnetic uniform field of b= 3 (i) + 4 (j) - 1 (k)

5rhe potential energy in mJ ?

is given by the dot product of u and b , correct? so the answer should be 11.4 , no ? or 539 ?

3 - 2 , 1 km wires ( so acting like infinite wires ) , both have same current , no direction specified , , separated by 1 meter distance and having between them a magnetic force of module 0.02 N . so the current value is 0.01???

the definition of 1 ampere has same conditions except the force between should be 2*10^-7 , so 2*10^-2

so 2*10^5 amps ???

last one of this thread ( couple of more threads coming up on different topics, been saving up almost a months worth of questions lol )

last one - charged particule reaches a uniform magnetic B field and velocity v , forming an a angle with the magnetic field . what is the expression of the relation , expressed as a ratio, of the radius and helical trajectory of the particule.

4 choices , all containing same term on the left side of the equation r/Ph=

a- 2pi/tan a

b- 1/2pi tan a

c- 2pi tan a

d- tan a / 2pi

so if particle , which is at rest, is subjected to a difference of potential of 15000 volts , over a 1cm distance, then enter the magnetic field b= . over a distance of 2cm. what will be its vertical displacement over 20cm .

gunning for d on this one, as the answer i ended after substitution and bit of algebra had cosine on the bottom .

although i cant figure out where they put the mass in that expression .

Please can anyone confirm my choice or say if theyre wrong? , i can justify my reasoning behind the choices , but each question is worded the exact same way which is the reason why im hesitating before submitting these answers .

thank you !

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