8. 9. A monochromatic light of wavelength 6500 is used in YDSE. Now both slits are covered by two thin slab of refractive index 3.2 and 2.7 respectively. By doing so central bright fringe shifts to original 7th bright fringe. If both slabs have same thickness then thickness of slab is (in m). A hollow sphere (mass m, radius R) is put inside a hollow cone (mass m, radius 3R and semi-angle 30) as shown in the figure. The whole arrangement is rigidly fixed to the ground at the apex of the cone. Both the sphere and the cone are made of the same material (a = 104/C). Considering that major changes in dimensions could happen only due to heating effects, find the increase in potential energy (in Joule) of the system if it's temperature is increased by 100C. m = 0.5kg 3-1 R m 2 10. A rod is clamped at both of its ends and stationary longitudinal waves are produced in it. In first experiment, the rod has a total of 4 nodes with amplitude of each anti-node to be 1mm. In other experiment, the rod has a total of 6 nodes with amplitude of each anti node to be 2mm. The energy of vibrations in the rod in two case is E and E respectively. Write value of E