A double charged lithium atom is equivalent to hydrogen whose atomic number is 3. The wavelength of required radiation for emitting electron from first to third Bohr orbit in 
will be (Ionisation energy of hydrogen atom is 13.6eV)
|
(a) 182.51 Å |
(b) 177.17 Å |
(c) 142.25 Å |
(d) 113.74 Å |
(d) 113.74 Å
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Two metallic spheres of radii 1 cm and 2 cm are given charges 
and 5 × respectively. If they are connected by a conducting wire, the final charge on the smaller sphere is
|
(a) 3 |
(b) 1 |
(c) 4 |
(d) 2 |
1 mg gold undergoes decay with 2.7 days half-life period, amount left after 8.1 days is
|
(a) 0.91 mg |
(b) 0.25 mg |
(c) 0.5 mg |
(d) 0.125 mg |
A person is suffering from the defect astigmatism. Its main reason is
|
(a) Distance of the eye lens from retina is increased |
|
(b) Distance of the eye lens from retina is decreased |
|
(c) The cornea is not spherical |
|
(d) Power of accommodation of the eye is decreased |
Assertion : Blue colour of sky appears due to scattering of blue colour.
Reason : Blue colour has shortest wave length in visible spectrum.
|
(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
|
(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
|
(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |
In the adjoining circuit, the e.m.f. of the cell is 2 volt and the internal resistance is negligible. The resistance of the voltmeter is 80 ohm. The reading of the voltmeter will be
|
(a) 0.80 volt |
(b) 1.60 volt |
(c) 1.33 volt |
(d) 2.00 volt |
Which of the following statements is incorrect about hysteresis
|
(a) This effect is common to all ferromagnetic substances |
|
(b) The hysteresis loop area is proportional to the thermal energy developed per unit volume of the material |
|
(c) The hysteresis loop area is independent of the thermal energy developed per unit volume of the material |
|
(d) The shape of the hysteresis loop is characteristic of the material |
Name of the India's first nuclear reactor is
|
(a) RAMBHA |
(b) MENAKA |
(c) URVASI |
(d) APSARA |
