MCQs of Ultrasonic and Non distractive testing (NDT) (Physics Group - I - 3110011)

Physics Group - I (3110011) MCQs

MCQs of Ultrasonic and Non distractive testing (NDT)

Showing 11 to 20 out of 38 Questions

11.

In magnetostriction effect, the bar undergoes alternate contractions and expansions at a frequency equal to the frequency of the applied

(a)	electromagnetic ray
(b)	electric field
(c)	magnetic field
(d)	thermal field

12.

For ultrasonic wave generation, on application of external magnetic field, the

(a)	natural frequency of the rod changes
(b)	applied frequency of the rod changes
(c)	cross-sectional area of the rod changes
(d)	length of the rod changes

13.

For magnetostriction generator, the generated frequency should be equal to

(a)	natural frequency
(b)	applied frequency
(c)	ultrasonic frequency
(d)	magnetostriction frequency

14.

The equation to find the frequency of ultrasonic waves produced by magnetostriction method is

(a)	$f = \frac{1}{2} \sqrt{\frac{Y}{ρ}}$
(b)	$f = \frac{1}{2 l} \sqrt{\frac{5 Y}{ρ}}$
(c)	$f = \frac{1}{2 l} \sqrt{\frac{Y}{ρ}}$
(d)	$f = \frac{1}{2} \sqrt{\frac{Y}{V}}$

15.

development of heat - tissues or water absorb the ultrasound energy which increases their __________ locally

(a)	frequency
(b)	temperature
(c)	magnetization
(d)	amplitude

16.

Magnetostriction method produces ultrasonic waves upto frequency

(a)	$3 x 10^{8} H z$
(b)	$3 x 10^{6} H z$
(c)	$3 x 10^{3} H z$
(d)	$3 x 10^{9} H z$

17.

The frequency of oscillations in __________ method depends on temperature.

(a)	magnetostriction
(b)	piezoelectric
(c)	thermal
(d)	all of these

18.

When __________ is applied to a pair of opposite faces of crystal like quartz, equal and opposite charges appears on the other faces.

(a)	heat
(b)	magnetic field
(c)	pressure
(d)	ultrasonic wave

19.

When an alternating voltage is applied on a pair of opposite faces of piezoelectric crystal (quartz), it starts vibrating at the frequency of the applied voltage. This is called

(a)	Piezoelectric effect
(b)	Inverse Piezoelectric effect
(c)	Magnetostriction effect
(d)	Modified effect

20.

We can generate ultrasonic waves up to 500 MHz using which method?

(a)	Mechanical generator
(b)	Galton's whistle
(c)	Piezoelectric generator
(d)	Magnetostriction generator

Showing 11 to 20 out of 38 Questions