Answer:
B. i=2.79A
C. F=0.066N
Explanation:
A) By the right hand rule we have that
F=iL x B
F=iLBsin(α)
If the wire jump toward the observer the top pole face is the magnetic southpole.
B) The diameter of the pole face is 15cm. We can take this value as L (the length in which the wire perceives the magnetic field). Hence, we have
[tex]F=iLBsin(\alpha)\\\alpha=90°\\F=iLB\\i=\frac{F}{LB}=\frac{6.71*10^{-2}N}{(0.15m)(0.16T)}=2.79A[/tex]
C) Now the length of the wire that feels B is
[tex]L=\frac{0.15m}{cos(10\°)}=0.152m[/tex]
and the force will be (by taking the degrees between the magnetic field vector and current vector as 80°)
[tex]F=iLBsin(\alpha)\\F=(2.79A)(0.152m)(0.16T)(sin(80\°))=0.066N[/tex]
I hope this is useful for you
regards