1. In Young’s double slit experiment the angular position of a point on the central maxima whose intensity is one fourth of maximum intensity
(A) sin-1(λ/d) (B)sin-1(λ/2d)
2. Ratio of area of hole to beaker is 0.1. Height of liquid in beaker is 3m, and hole is at the height of 52.5 cm from the bottom of beaker, find the square of the velocity of liquid coming out from the hole
(A) 50 (m/s)² (B) 50.5 (m/s)²
(C) 51 (m/s)² (D) 42 (m/s)²
3. A cylindrical conducting rod is kept with its axis along positive z-axis, where a uniform magnetic field exists
parallel to z-axis. The current induced in the cylinder is
(A) zero (B) clockwise as seen from +z axis
(C) anti-clockwise as seen from +z axis (D) opposite to the direction of magnetic field.
4. A particle is confined to rotate in a circular path with decreasing linear speed, then which of the following is correct?
(A) L(angular momentum) is conserved about the centre.
(B) only direction of angular momentum L is conserved.
(C) It spirals towards the centre.
(D) its acceleration is towards the centre.
5. The atomic number (Z) of an element whose kα wavelength is λ is 11. The atomic number of an element whose
kα wavelength is 4λ is equal to
(A) 6 (B) 11
(C) 44 (D) 4
Source 2005 JEE screening