An electron of mass m and charge e is accelerated from rest through a potential difference V in vacuum. The final speed of the electron will be
|
(a) |
(b) |
(c) |
(d) 2eV/m |
(c) 
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In the given figure, when key K is opened, the reading of the ammeter A will be
|
(a) 50 A |
(b) 2 A |
(c) 0.5 A |
(d) |
If a dielectric substance is introduced between the plates of a charged air-gap capacitor. The energy of the capacitor will
|
(a) Increase |
(b) Decrease |
|
(c) Remain unchanged |
(d) First decrease and then increase |
Voltmeters V1 and V2 are connected in series across a D.C. line. V1 reads 80 volts and has a per volt resistance of 200 ohms. V2 has a total resistance of 32 kilo ohms. The line voltage is
|
(a) 120 volts |
(b) 160 volts |
(c) 220 volts |
(d) 240 volts |
A coil having 500 square loops each of side 10 cm is placed normal to a magnetic flux which increases at the rate of 1.0 tesla/second. The induced e.m.f. in volts is
|
(a) 0.1 |
(b) 0.5 |
(c) 1 |
(d) 5 |
The patient is asked to drink 
for examining the stomach by X-rays because X-rays are
|
(a) Reflected by heavy atoms |
(b) Refracted by heavy atoms |
|
(c) Less absorbed by heavy atoms |
(d) More absorbed by heavy atoms |
The wavelength of light visible to eye is of the order of
|
(a) |
(b) |
(c) 1 m |
(d) 6 |
