In this article we are sharing CDS Written Exam Practice Problems: Physics.
CDS Written Exam Practice Problems: Physics
| 1. Confirmation of presence of Higgs Boson will justify | |
| a. Both the standard model and super-string theory | |
| b. The unification of all the four fundamental forces | |
| c. The steady-state model of the universe | |
| d. The mass of the fundamental particle | |
| Solution. Confirmation of presence of Higgs Boson will justify both the standard model and superstring theory | |
| Answer. a |
| 2. In terms of magnetic properties, oxygen belong to | |
| a. Magnetic materials | |
| b. Ferromagnetic materials | |
| c. Paramagnetic material | |
| d. Diamagnetic material | |
| Solution. By molecular orbital theory, oxygen is a Para-magnetic molecule having two unpaired electrons. | |
| Answer. c |
| 3. Light Emitting Diode (LED) converts | |
| a. Light energy into electrical energy | |
| b. Electrical energy into light energy | |
| c. Thermal energy into electrical energy | |
| d. Mechanical energy into electrical energy | |
| Solution. A light-emitting diode (LED) is a two-lead semiconductor light source that resembles a basic pn-junction diode, except that an LED also emits light. | |
| Answer. b |
| 4. The Celsius temperature is a/an | |
| a. Relative temperature | |
| b. Absolute temperature | |
| c. Specific temperature | |
| d. Approximate temperature | |
| Solution. The degree Celsius (°C) can refer to a specific temperature on the Celsius scale as well as a unit to indicate a temperature interval, a difference between two temperatures.
Absolute temperature is the temperature of an object on a scale where 0 is taken as absolute zero, or the temperature where there is zero thermal energy in a sample of matter. | |
| Answer. c |
| 5. The gas used in a refrigerator is | |
| a. Cooled down on flowing | |
| b. Heated up on flowing | |
| c. Cooled down when compressed | |
| d. Cooled down when expanded | |
| Solution. Adiabatic cooling occurs when the pressure of a substance is decreased as it does work on its surroundings. Expansion decreases pressure. | |
| Answer. d |
| 6. If two conducting spheres are separately charged and then bought in contact | |
| a. The total energy of the two sphere is conserved | |
| b. The total charge on the two spheres is conserved | |
| c. Both the total energy and the total charge are conserved | |
| d. the final potential is always the mean of the original potential of the two spheres | |
| Solution. According to the law of conservation of charges, total energy is conserved. | |
| Answer. b |
| 7. Which type/types of pen uses/use capillary action in addition to gravity for flow of ink? | |
| a. Fountain pen | |
| b. Ballpoint pen | |
| c. Gel pen | |
| d. Both ballpoint and gel pen | |
| Solution. Capillary action (sometimes capillarity, capillary motion, or wicking) is the ability of a liquid to flow in narrow spaces without the assistance of, and in opposition to, external forces like gravity, fountain pen uses this action. | |
| Answer. a |
| 8. A device, which is used in our TV set, computer, radio set for storing the electric charge, is | |
| a. Resistor | |
| b. Inductor | |
| c. Capacitor | |
| d. Conductor | |
| Solution. A capacitor (originally known as a condenser) is a passive two-terminal electrical component used to store energy electrostatically in an electric field. | |
| Answer. c |
| 9. A bus travels at a speed of 50 km/h to go from its origin to its destination at a distance of 300 km, and travels at a speed of 60 km/h to return to the origin. What is the average speed of the bus? | |
| a. 54.55 km/h | |
| b. 55 km/h | |
| c. 55.55 km/h | |
| d. 54 km/h | |
| Solution. Average speed = (total distance)/ (total time) Total distance = 300+300 =600 Total time = 300/50 +300/60 =6+5= 11hr Hence, average speed = 600/11= 54.55 km/hr. | |
| Answer. a |
| 10. When deep sea fishes are brought to the surface of the sea, their bodies burst. This is because the blood in their bodies flow at very | |
| a. High speed | |
| b. High pressure | |
| c. Low speed | |
| d. Low pressure | |
| Solution. The lower you go in the sea, the greater the water pressure, because of all the water above you, pressing down with its weight. To avoid being crushed by the water pressure, fish have an internal body pressure that is equal to that of the external water pressure.
When the fish are raised to the surface rapidly, their internal pressure then is much greater than the air pressure, and it can cause their bodies to burst. If they are raised more slowly, the pressure has a chance to equalize (Exactly the same reasoning to explain why an astronaut’s body would burst if he forgot to get into his space suit before he stepped out on the veranda and began a spacewalk). | |
| Answer. b |
