MCQ
The first spectral series was disscovered by:
- ABalmer.
- BLyman.
- CPaschen.
- DPfund.
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A Young's double slit experiment uses a monochromatic source. The shape of the interference fringes formed on a screen is
|
(a) Straight line |
(b) Parabola |
(c) Hyperbola |
(d) Circle |
One conducting U tube can slide inside another as shown in figure, maintaining electrical contacts between the tubes. The magnetic field B is perpendicular to the plane of the figure. If each tube moves towards the other at a constant sped v then the emf induced in the circuit in terms of B, l and v where l is the width of each tube, will be

|
(a) Zero |
(b) 2 Blv |
(c) Blv |
(d) -Blv |