Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

The thermocouple is based on the principle of

(a) Seebeck effect

(b) Thomson effect

(c) Peltier effect

(d) Joule effect

The particle that possesses half integral spin as

(a) Photon

(b) Pion

(c) Proton

(d) K-meson

Two resistances of 400 W and  800 W are connected in series with 6 volt battery of negligible internal resistance.  A voltmeter of resistance 10,000 W is used to measure the potential difference across 400 W.  The error in the measurement of potential difference in volts approximately is

(a) 0.01

(b) 0.02

(c) 0.03

(d) 0.05

Brewster's law is :

A caesium photocell, with a steady potential difference of 60V across, is illuminated by a bright point source of light 50 cm away. When the same light is placed 1m away the photoelectrons emitted from the cell

(a) Are one quarter as numerous

(b) Are half as numerous

(c) Each carry one quarter of their previous momentum

(d) Each carry one quarter of their previous energy

E denotes electric field in a uniform conductor, I corresponding current through it,  drift velocity of electrons and P denotes thermal power produced in the conductor, then which of the following graph is incorrect

(a)

(b)

(c)

(d)

The impedance of a series L - C - R circuit in an AC circuit is.

A particle is moving in a uniform magnetic field, then

(a) Its momentum changes but total energy remains the same

(b) Both momentum and total energy remain the same

(c) Both will change

(d) Total energy changes but momentum remains the same

Two cells when connected in series are balanced on 8m on a potentiometer. If the cells are connected with polarities of one of the cell is reversed, they balance on 2m. The ratio of e.m.f.'s of the two cells is

(a) 3 : 5

(b) 5 : 3

(c) 3 : 4

(d) 4 : 3

Antimony and bismuth are usually used in a thermocouple, because

(a) Negative thermal e.m.f. produced	(b) Constant thermal e.m.f. produced
(c) Lower thermal e.m.f. produced	(d) Higher thermal e.m.f. produced