In Fresnel’s biprism experiment, on increasing the prism angle, fringe width will
|
(a) Increase |
(b) Decrease |
|
(c) Remain unchanged |
(d) Depend on the position of object |
(b) Decrease
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In the following circuit a 10 m long potentiometer wire with resistance 1.2 ohm/m, a resistance R1 and an accumulator of emf 2 V are connected in series. When the emf of thermocouple is 2.4 mV then the deflection in galvanometer is zero. The current supplied by the accumulator will be
|
(a) 4 × 10–4 A |
(b) 8 × 10–4 A |
(c) 4 × 10–3 A |
(d) 8 × 10–3 A |
Condenser A has a capacity of 15μF when it is filled with a medium of dielectric constant 15. Another condenser B has a capacity of 1 μF with air between the plates. Both are charged separately by a battery of 100 V. After charging, both are connected in parallel without the battery and the dielectric medium being removed. The common potential now is
|
(a) 400 V |
(b) 800 V |
(c) 1200 V |
(d) 1600 V |
Energy of photon whose frequency is 
, will be
|
(a) 4.14 |
(b) 4.14 |
(c) 4.14 |
(d) 4.14 |
The mass of an a-particle is
|
(a) Less than the sum of masses of two protons and two neutrons |
|
(b) Equal to mass of four protons |
|
(c) Equal to mass of four neutrons |
|
(d) Equal to sum of masses of two protons and two neutrons |
When a piece of aluminium wire of finite length is drawn through a series of dies to reduce its diameter to half its original value, its resistance will become
|
(a) Two times |
(b) Four times |
(c) Eight times |
(d) Sixteen times |
Three capacitors are connected to D.C. source of 100 volts shown in the adjoining figure. If the charge accumulated on plates of 
and 
are 
and 
respectively, then
|
(a) |
(b) |
|
(c) |
(d) |
