Question

treating the heart as a box that is L = 13.0 cm long and W = 10.0 cm wide, calculate the magnitude of the maximum torque on the current loop. suppose a patients pacemaker implants requires I = 1.8 mA of current to function. the leads of the device travel close together until they reach the heart and then split off to touch the top and bottom of the heart, such that size of the current loop is approximately half the cross-sectional area of the heart. Suppose the MRI machine uses a magnetic field of B = 1.0 T.

Magnetic resonance imaging (MRI) scans are often prohibited for patients with an implanted device, such as a pacemaker. There are multiple reasons for this prohibition. One reason is the physical torque on the device due to the MRI's magnetic field. Suppose a patient's pacemaker implant requires 1 1.8 mA of current to function. The leads of the device travel close together until they reach the heart and then split off to touch the top and bottom of the heart, such that size of the current loop is approximately half the cross-sectional area of the heart. Suppose the MRI machine uses a magnetic field of B1.0T Treating the heart as a box that is L = 13.0 cm long and W-10.0 cm wide, calculate the magnitude of the maximum torque τ on the current loop x10 N·m

Answer 1

The area of the current loop is half of the area of the box (heart). Hence, LW (0.13m)(0.1 m) =6.5×10-3 ㎡ The magnitude of the torque on the current loop is, For the maximum torque, sin6-1 Hence, the magnitude of the maximum torque on the current loop is as follows -(1)(1.8x10 A (65x10m)1.0T) =1.17 x 105 N-m