[{"id":146048,"question":"The temperature at which the speed of sound becomes double as was at 27<b style=\"color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;\">°</b>C is","choices":[{"text":"273<b style=\"color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;\">°</b>C","value":"A"},{"text":"0<b style=\"color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;\">°</b>C","value":"B"},{"text":"927<b style=\"color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;\">°</b>C","value":"C"},{"text":"1027<b style=\"color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;\">°</b>C","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":146047,"question":"Two sources of sound are said to be coherent if","choices":[{"text":"They produce sounds of equal intensity","value":"A"},{"text":"They produce sounds of equal frequency","value":"B"},{"text":"They produce sound waves vibrating with the same phase","value":"C"},{"text":"They produce sound waves with zero or constant phase different all instant of time","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146046,"question":"When sound waves travel from air to water which of these remains constant?","choices":[{"text":"Velocity","value":"A"},{"text":"Frequency","value":"B"},{"text":"Wavelength","value":"C"},{"text":"All the above","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":146045,"question":"In a simple harmonic motion the kinetic energy (KE) and the potential energy (PE), are such that throughout the motion","choices":[{"text":"KE remains constant","value":"A"},{"text":"PE remains constant","value":"B"},{"text":"KE/PE is constant","value":"C"},{"text":"KE+PE remains constant","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146044,"question":"A pendulum clock set to give correct time in Karachi is taken to Quetta. It would give correct time if","choices":[{"text":"The mass of the pendulum is increased","value":"A"},{"text":"The mass of the pendulum is decreased","value":"B"},{"text":"The length of the pendulum is increased","value":"C"},{"text":"The length of the pendulum is decreased","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146043,"question":"In a simple harmonic motion (SHM), which of the following does not hold?","choices":[{"text":"To force on the particle is maximum at the ends","value":"A"},{"text":"The acceleration in minimum at the mean position","value":"B"},{"text":"The potential energy is maximum at the mean position","value":"C"},{"text":"The kinetic energy is maximum at the mean position","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":146042,"question":"To make the frequency double of an oscillator, we have to","choices":[{"text":"Double the mass","value":"A"},{"text":"Half the mass","value":"B"},{"text":"Quadruple the mass","value":"C"},{"text":"Reduce the mass to one fourth","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146041,"question":"The time period of a simple pendulum is 2 seconds. If its length is increased by 4 times, then its period becomes","choices":[{"text":"16 s","value":"A"},{"text":"12 s","value":"B"},{"text":"8 s","value":"C"},{"text":"4 s","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146040,"question":"If the period of oscillation of mass (M) suspended from a spring is 2s, then the period of mass 4M will be","choices":[{"text":"1 s","value":"A"},{"text":"2 s","value":"B"},{"text":"3 s","value":"C"},{"text":"4 s","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146039,"question":"If the metal bob is a simple pendulum is replaced by a wooden bob, then its time period will","choices":[{"text":"Increas","value":"A"},{"text":"Decreases","value":"B"},{"text":"Remain the same","value":"C"},{"text":"First A then B","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":146038,"question":"In Which case does the potential energy decreases?","choices":[{"text":"On compressing a spring","value":"A"},{"text":"On stretching a spring","value":"B"},{"text":"One moving a body against gravitational force","value":"C"},{"text":"One the rising of an air bubble in water","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146037,"question":"Which one of the following is a simple harmonic motion?","choices":[{"text":"Wave moving through a string fixed at both ends","value":"A"},{"text":"Earth spinning about its own axis","value":"B"},{"text":"Ball bouncing between two rigid vertical walls","value":"C"},{"text":"Particle moving in a circle with uniform speed","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146036,"question":"Blood has a density","choices":[{"text":"Equal to water","value":"A"},{"text":"Greater then water","value":"B"},{"text":"Lesser then water","value":"C"},{"text":"None of these","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146035,"question":"The smooth or steady stream-line flow is know as","choices":[{"text":"Laminar flow","value":"A"},{"text":"Turbulent flow","value":"B"},{"text":"Both a and b","value":"C"},{"text":"None of the above","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146034,"question":"According to Stoke's law, drag force depends on","choices":[{"text":"Initial velocity","value":"A"},{"text":"Final velocity","value":"B"},{"text":"Terminal velocity","value":"C"},{"text":"Instantaneous velocity","value":"D"},{"value":"E"}],"correctAnswer":4}]