19.A radioactive -emission. A detector records n -particles in 2s and by next 2s (accumulatively) it records 1.1 n -particle. Number of -particles recorded by detector after a long time, is (1) 11n 10 (3) 2n 12n 10 10n 20.Consider the given arrangement. The two slits S and S2 are illuminated by monochromatic light of wavelength 2. Slits S3 and S4 are at separation d be AD 3d then ratio of maximum and minimum intensity on the screen will (1)9 1 (3) 4:1 Failisha SA S D D Screen (2) 8:1 (4) 2:1 21.The given arrangement is in vertical plane and initially the springs are in natural length. The uniform rod is hinged at end 0, about which it can freely rotate. The angular frequency of small oscillations of the rod is Find n. (Given: m = mass of rod, L = length of rod and k = L m k www 22. Three capacitors each of capacitance C = 2F are connected with a battery of emf 30V as shown in the figure. When the switch S is closed, the heat generated in circuit will be my. Find the value of n. 10 HH 10 30 V