An aircraft part may be demagnetized by subjecting it to a magnetizing force from alternating current that is gradually reduced in strength.
(2) An aircraft part may be demagnetized by subjecting it to a magnetizing force from direct current that is alternately reversed in direction and gradually reduced in strength.
Regarding the above statements,

1) an aircraft part my be demagnetized by subjecting it to a magnetizing force from alternating current that is gradually reduced in strength.

2) an aircraft part may be demagnetized by subjecting it to a magnetizing force from direct current that is alternately reversed in direction and gradually reduced in strength.regarding the above statements.

A. Both no. 1 and no. 2 are true

B. Only no. 1 is true

C. Only no. 2 is true

The correct answer is

A. Both no. 1 and no. 2 are true

Explanation:

After performing inspection such as magnetic particle inspection, the part should be demagnetized before being put to use to prevent them from accumulating metal chips and grindings left behind from maintenance activities or wear of the metal parts

There are different methods of demagnetization, however an appropriate procedure centers on subjecting it to a repeatedly reversing magnetizing force while simultaneously gradually reducing the strength of the introduced magnetizing force. That is, applying the decreasing magnetizing force from north to south pole, then from south to north poles decreases the magnetization of the part

The above procedure can be achieved by applying an alternating current energized solenoid coil of comparable size to the part and gradually moving or separating the part and the solenoid to up to two feet apart resulting to the demagnetization of the part.

a electromagnetic waves