An electron beam is moving between two parallel plates having electric field 1.125 
. A magnetic field 3 
is also applied so that beam of electrons do not deflect. The velocity of the electron is
|
(a) 4225 m/s |
(b) 3750 m/s |
(c) 2750 m/s |
(d) 3200 m/s |
(b) 3750 m/s
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The impact of an image on the retina remains for
|
(a) 0.1 sec |
(b) 0.5 sec |
(c) 10 sec |
(d) 15 sec |
A man wearing glasses of focal length +1m cannot clearly see beyond 1m:
Electric lines of force about negative point charge are
|
(a) Circular, anticlockwise |
(b) Circular, clockwise |
|
(c) Radial, inward |
(d) Radial, outward |
The example of nuclear fusion is
|
(a) Formation of Ba and Kr from U235 |
|
(b) Formation of He from H |
|
(c) Formation of Pu – 235 from U - 235 |
| (d) Formation of water from hydrogen and oxygen |
Switch S of the circuit shown in figure. is closed at t = 0. If e denotes the induced
emf in L and i, the current flowing through the circuit at time t, which of the following graphs is correct
|
(a)
|
(b)
|
(c)
|
(d)
|
Einstein's photoelectric equation states that 
. In this equation 
refers to
|
(a) Kinetic energy of all the emitted electrons |
|
(b) Mean kinetic energy of the emitted electrons |
|
(c) Maximum kinetic energy of the emitted electrons |
|
(d) Minimum kinetic energy of the emitted electrons |
Decay constant of radium is λ. By a suitable process its compound radium bromide is obtained. The decay constant of radium bromide will be
|
(a) λ |
(b) More than λ |
(c) Less than λ |
(d) Zero |
An electromagnetic wave, going through vacuum is described by
. Which of the following is independent of wavelength
| (a) k | (b) w | (c) k/w | (d) kw |
A negatively charged plate has charge density of 2 
. The initial distance of an electron which is moving toward plate, cannot strike the plate, if it is having energy of 200 eV
|
(a) 1.77 mm |
(b) 3.51 mm |
(c) 1.77 cm |
(d) 3.51 cm |
