The TV transmission tower at a particular station has a height of 125 m. For doubling the coverage of its range, the height of the tower should be increased by (a) 125m (b) 250m (c) 375m (d) 300m 12. The motion of a simple pendulum executing S.H.M. is represented by the following equation. y=Asin(t+), where time is measured in second. The length of pendulum is (a) 97.23 cm (b) 25.3 cm (c) 99.4 cm (d) 406.1 cm A vessel contains 16g of hydrogen and 128g of oxygen at standard temperature and pressure. The volume of the vessel in cm is: (a) 72 x 105 (b) 32 x 105 14. Given below are two statements: (c) 27 x 104 (d) 54 x 104 Statement I: The electric force changes the speed of the charged particle and hence charges its kinetic energy; whereas the magnetic force does not change like kinetic energy of the charged particle. Statement II: The electric force accelerates the positively charged particle perpendicular to the direction of electric field. The magnetic force accelerated the moving charged particle along the direction of magnetic field. In the light of the above statements, chose the most appropriate answer from the option given below: (a) Both Statement I and Statement II are correct. (b) Both Statement I and Statement II are incorrect. (c) Statement I is correct but Statement II is incorrect. (d) Statement I is incorrect but Statement II is correct. 15. A block of mass 40kg slides over a surface, when a mass of 4kg is suspended through an inextensible massless string passing over frictionless pulley as shown below. The coefficient of kinetic friction between the 40 kg surface and block is 0.02. The acceleration of block is. (given g = 10 ms-2.) (a) 1 ms (b) 1/5 ms-2 (c) 4/5 ms-2 4 kg Activ Go to (d) 8/11 ms-2