Question

Respiratory inductance plethysmography (RIP) is a method of monitoring breathing. Elastic bands with an internal 200-turn coil are placed around the rib cage. During inspiration the cross-sectional area of the rib cage and area encircled by the belt increase by 39.0 cm^2. The magnitude of the Earth’s magnetic field is 50.0 mirco T and makes an angle of 28.0 with the plane of the coil. Assuming a patient inspiration takes 1.80 s, find the magnitude of the average induced emf in the coil during that time.

Answer 1

Induced emf is given by V = -?/?t

is magnetic flux given by nBAcos ,B is magnetic field

A is area and is angle between B and A

= 200×50×10^-3×A×cos28

= 8.83A

-?/?t = -8.83(?A/?t)

= -8.83(39×10^-4/1.80)

= 1.913×10^-2 volt