11 Choose the correct option 1 1 AU 9 46 x 1015 m 2 1 A 10 8 cm 3 1 ly 3 26 Parsec 4 1 Parsec 1 496 10 1 m 12 The weakest fundamental force is 1 Strong nuclear force 2 Weak nuclear force 3 Electromagnetic force 4 Gravitational force 13 The parallax of a far off star as measured from two diametric extremes on the equator of the earth is 1 minute of arc If radius of earth is 6400 km then the distance of the star from the earth is 1 44 x 106 km 3 11 x 106 km 2 22 x 106 km 4 33 x 106 km 14 If the dimensions of a physical quantity are given by Ma Lb Tc then the physical quantity will be 1 Work if a 1 b 1 c 2 2 Time if a 0 b 1 c 1 3 Surface tension if a 1 b 0 c 2 4 Velocity if a 0 b 1 c 1 15 If force F velocity V and time 7 are taken as fundamental quantities the dimensional formula for energy will be 1 F V T 3 F VT 16 Zero error in an instrument introduces 1 Random error 2 Personal error 3 Least count error 4 Systematic error 17 If a number 4 732615 is to be 2 FVT 4 F V T 1 4 732 3 4 733 unded off up to three significant figures then the new number will be 20 If the units of mass length and time each are doubled then the unit of velocity will be 2 4 73 4 4 7 18 Which of the following is not the unit of time 1 Shake 2 Barn 4 Second 3 Year 19 The diameter of a cup is measured using a vernier caliper The 20 vernier scale divisions are equal to 18 main scale divisions If one division of main scale is x mm then least count of the instrument is x 21 The least count of a stopwatch is 0 2 s the time of 100 oscillations is found to be 200 s percentage error in the The maximum measurement of time is 1 10 3 0 2 22 1 Doubled 2 Halved 3 Tripled 4 Remains same For a systematic error which of the following graph is correct 2 24 Error Raka Error Error Error dical I JEF No of observations 23 An object travels 20 m in 4 s and then another 20 m in next 10 s then choose the correct option 7 2 0 1 4 5 No of observations m s No of observations 1 Average velocity for entire journey must be 20 No of observations m s 2 Average speed for entire journey must be 20 7 15 3 Average velocity for entire journey must be zero 4 Average speed for entire journey must be zero The distance travelled by an object star from rest and moving with an accel m s in the 3rd second is 15