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381.

When a loop composed of two dissimilar metals could be made to carry a continuous current simply by maintaining the two junctions at different temperatures, the above effect is known as

A.	Thomson effect	B.	Thompson effect
C.	Peltier effect	D.	Seeback effect

382.

A thermocouple works on which of the following effect?

A.	Thomson effect	B.	Seeback effect
C.	Peltier effect	D.	Joule effect

383.

When a current is passed through the junction of two different metals, heat is absorbed or liberated depending on the direction of the current. The above phenomenon is known as

A.	Kelvin effect	B.	Joule's effect
C.	Peltier's effect	D.	None of the above

384.

Which of the following material can be used at temperatures above 100?C?

A.	Polythene	B.	Teflon
C.	Rubber	D.	Paraffin wax

385.

Which of the following materials can be used for temperatures upto 500?C?

A.	Empire cloth	B.	Paper oiled
C.	Mica	D.	Polythene

386.

Which of the following is the ferroelectric material?

A.	Rechelle salt	B.	Barium titanate
C.	Potassium dehydrogen phosphate	D.	All of the above

387.

The Curic point for Rochelle salt is about

A.	1000?C	B.	500?C
C.	240?C	D.	Absolute zero

388.

Materials which lack permanent magnetic dipoles are called

A.	diamagnetic	B.	ferromagnetic
C.	semi-magnetic	D.	None of the above

389.

When the atomic magnetic moments are randomly oriented in a solid, its magnetic behaviour is termed as

A.	polycrystalline	B.	anti-ferromagnetic
C.	paramagnetic	D.	semi-magnetic

390.

The structure of a semi-conductor resemles that of a

A.	circle	B.	rhombus
C.	diamond	D.	triangle