B1 = 1.17x10-4 T,
τ = 50x10-6 s, and
B1 is applied along the +x' axis.
The relationship between the rotation angle in radians (θ) and the length, in seconds, that the B1 field is applied (τ) is:
where: γ = gymagnetic ratio for the nuclei in question.
θ = 2π * 50x10-6s * 1.17x10-4T * 42.58 MHz/T
θ = 1.565 rad.
θ = 1.565 rad. * 180o/π rad = 89.673o
The net magnetization vector will be almost along the +y' axis: 89.673o from the +z axis after the clockwise about the +x' axis.