An MRI technician moves his hand from a region of very low magnetic field strength into an MRI scanner’s 1.7 T field with his fingers pointing in the direction of the field. (a) Find the average emf induced in his wedding ring, given its diameter is 2.4 cm and assuming it takes 0.2 s to move it into the field.

0.004 V or 4 mV

Explanation:

Parameters given:

Magnetic field, B = 1.77 T

Number of turns, N = 1

Diameter = 2.4 cm ; Radius, r = 1.2cm = 0.012 m

Time taken, t = 0.2 s

Induced EMF is given as:

EMF = (B * pi * r² *N) / t

EMF = (1.77 * 3.142 * 0.012² * 1) / 0.2

EMF = 0.004 V = 4 mV

nec chapter 5 contains

c. information on special occupancy areas

nec chapter 6 covers

a. special equipment

which of the following rules contain the words shall or shall not and must be adhered to?

b. mandatory rules

which of the following rules identify actions that are allowed but not required and typically cover options or alternative methods?

c. optional rules

which of the following serves as the introduction to the nec and provides an overview of the book?

a. nec article 90

organizations that test products for safety are

c. nrtls

the nec is published by the

a national fire protection association

the nec is divided into

b. 9 chapters

the nec provides informative annexes for

c. informational materials and examples

two terms from nec article 100 that trainees should become familiar with are

b. labeled and listed

explanation: