1. A particle is executing simple harmonic motion with a time period T. At time t=0, it is at its position of equilibrium. The kinetic energy-time graph of the particle will look like: KE (1) (3) KE T/2 T (2) T/4 T/2 m KE T/2 KE (4) # 2. The temperature of an open room of volume 30 m increases from 17C to 27C due to sunshine. The atmospheric pressure in the room remains 1 x 105 Pa. Ifn, and n, are the number of molecules in the room before and after heating, then n,-n, will be: (1) 2.51025 (3) -1.611023 (2) -2.51025 (4) 1.381023 3. Which of the following statements is false? (1) A rheostat can be used as a potential divider (2) Kirchhoff's second law represents energy conservation (3) Wheatstone bridge is the most sensitive when all the four resistances are of the same order of magnitude (4) In a balanced wheatstone bridge if the cell and the galvanometer are exchanged, the null point is disturbed. 4. The following observations were taken for determining surface tensiton T of water by capillary method: Diameter of capilary, D= 1.25 102 m rise of water, h 1.45 10-2m Using g=9.80 m/s and the simplified relation T = rhgx103 N/m, the possible error in surface tension is 2 closest to: (1) 2.4% (2) 10% (3) 0.15% (4) 1.5%