DCE (Delhi College of Engineering) Entrance Examination Sample Paper - Physics
DCE (Delhi College of Engineering) DCE Entrance Examination Sample Paper (Physics)
The question paper contains 180 questions. Four choices are given for a question out of which one choice may be correct. Each question carries 4 marks. The total marks of the Entrance Test are 720 (240 for each subject, i.e., Physics, Chemistry, Maths). You will get 4 marks for each correct response. For each incorrect response, one mark will be deducted from the total score. As such for each incorrect response, you will lose 5 marks (4 for wrong response and one mark as penalty).
1. Following two wave trains are approaching each other. |
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A. 8 |
B. 4 |
C. 1 |
D. 0 |
2. One of the geo-stationary satellites of India is vertically above |
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A. New Delhi |
B. Mumbai |
C. Allahabad |
D. None of these |
3. Light of wavelength 2400 x 10-10 m in air will become light of wavelength in glass (m = 1.5) equal to |
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A. 1600 x 10-10 m |
B. 7200 x 10-10 m |
C. 1080 x 10-10 m |
D. none of these |
4. The ratio of secondary to primary turns is 4:5. If power input is P, what will be the ratio of power output (neglect all losses) to power input ? |
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A. 4:9 |
B. 9:4 |
C. 5:4 |
D. 1:1 |
5. Lenz's law applies to |
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A. electrostatics |
B. lenses |
C. electro-magnetic induction |
D. cinema slides |
6. If a proton and anti-proton come close to each other and annihilate, how much energy will be released ? |
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A. 1.5 x 10-10 J |
B. 3 x 10-10 J |
C. 4.5 x 10-10 J |
D. none of these |
7. If Sn is doped with As, what will be the result ? |
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A. n-type semi-conductor |
B. p-type semi-conductor |
C. intrinsic semi-conductor |
D. none of these |
8. A charge is placed at the centre of a cube, what is the electric flux passing through one of its faces? |
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A. (1/6) x (q/e0) |
B. q/e0 |
C. 6q/e0 |
D. None of these |
9. What is the degree of freedom in case of a mono atomic gas ? |
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A. 1 |
B. 3 |
C. 5 |
D. None of these |
11. Speed of recession of galaxy is proportional to its distance |
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A. directly |
B. inversely |
C. exponentially |
D. none of these |
12. If a substance goes in a magnetic field and is pushed out of it, what is it ? |
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A. Paramagnetic |
B. Ferromagnetic |
C. Diamagnetic |
D. Antiferromagnetic |
13. Which is not a scalar quantity? |
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A. Work |
B. Power |
C. Torque |
D. Gravitational Constant |
14. Minimum energy required to excite an electron in a Hydrogen atom in ground state is : |
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A. -13.6 eV |
B. 13.6 eV |
C. 10.2 eV |
D. 3.4 eV |
15. If Gravitational Constant is decreasing in time, what will remain unchanged in case of a satellite orbiting around earth ? |
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A. Time period |
B. Orbiting radius |
C. Tangential velocity |
D. Angular velocity |
16. If a transparent medium of refractive index m = 1.5 and thickness t = 2.5 x 10-5 m is inserted in front of one of the slits of Young's Double Slit experiment, how much will be the shift in the interference pattern ? The distance between the slits is 5.0 x 10-3 cm and that between slits and screen is 100 cm. |
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A. 5 cm |
B. 2.5 cm |
C. 0.25 cm |
D. 0.1 cm |
17. How does light propagate in optical fibres? |
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A. Total internal reflection |
B. Refraction |
C. Reflection |
D. None of these |
18. Dispersion of light is due to |
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A. wavelength |
B. intensity of light |
C. density of medium |
D. none of these |
19. Which of the following conclusions is correct regarding a stationary body? |
A. No force is acting on the body |
B. Vector sum of forces acing on the body is zero |
C. The body is in vacuum |
D. The forces acting on the body do not constitute a couple |
20. Energy released in stars is due to |
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A. Fission |
B. Fusion |
C. Combustion |
D. Chemical reaction |
21. 13 days is the half-life period of a sample. After how many days, the sample will become 1/16th of the original substance ? |
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A. 52 |
B. 3.8 |
C. 3 |
D. none of these |
22. Absolute zero is the temperature at which |
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A. water solidifies |
B. all gases become liquid |
C. motion of molecules becomes minimum |
D. everything solidifies |
23. Motion of liquid in a tube is described by |
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A. Bernaulli's Theorem |
B. Poiseuille Equation |
C. Stoke's Law |
D. Archimedes' Principle |
24. Molecular motion shows itself as |
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A. Temperature |
B. Internal Energy |
C. Friction |
D. Viscosity |
25. Which is this gate ? |
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A. AND |
B. NAND |
C. OR |
D. NOR |
26. Energy bands in solids are a consequence of |
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A. Ohm's Law |
B. Pauli's Exclusion Principle |
C. Bohr's Theory |
D. Heissenberg's Uncertainty Principle |
27. A boy of mass M stands on the floor of an elevator moving downwards with an acceleration a which is less than g. The force exerted by the boy on the floor of the elevator is |
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A. Mg x Ma |
B. g + a |
C. Mg – Ma |
D. Mg + Ma |
28. A body A of mass m1 exerts a force on another body B of mass m2. If the acceleration of B be a2, then the acceleration (in magnitude ) of A is |
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A. m2/m1 (a2) |
B. m1m2 a2 |
C. m1/m2 (a2) |
D. (m1 + m2) a2 |
29. What does not change when sound enters from one medium to another ? |
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A. Wavelength |
B. Speed |
C. Frequency |
D. none of these |
30. Resolving power of a microscope depends upon |
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A. wavelength of light used, directly |
B. wavelength of light used, inversely |
C. frequency of light used |
D. focal length of objective |
31. An astronaut of weight Mg is in a rocket accelerating upward with an acceleration of 4g. The apparent weight of the astronaut will be |
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A. 5Kg |
B. 4Kg |
C. Mg |
D. zero |
32. One proton beam enters a magnetic field of 10-4 m/s normally, sp. charge = 1011 C/kg, velocity = 109 m/s. What is the radius of the circle describe by it ? |
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A. 0.1 m |
B. 100 m |
C. 10 m |
D. none of these |
33. If a black body radiates 20 calories per second at 227°C, it will radiate at 727°C |
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A. 10 calories per second |
B. 80 calories per second |
C. 320 calories per second |
D. none of these |
34. If a carnot engine is working with source temperature equal to 227°C and its sink temperature is at 27°C, its efficiency will be |
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A. 20% |
B. 10% |
C. 67% |
D. 50% |
35. If the frequency of an oscillating particle is n, then the frequency of oscillation of its potential energy is |
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A. n |
B. 2n |
C. n/2 |
D. 4n |
36. If an electron oscillates at a frequency of 1 GHz, it gives : |
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A. X-rays |
B. Micro-waves |
C. Infra-red rays |
D. None of these |
37. Earth's atmosphere is richest in |
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A. Ultra-violet rays |
B. Infra-red rays |
C. X-rays |
D. Micro-waves |
38. Cathode rays consist of |
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A. Photons |
B. Electrons |
C. Protons |
D. a -particles |
39. A body of mass m1 is moving with a velocity V. It collides with another stationary body of mass m2. They get embedded. At the point of collision, the velocity of the system |
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A. increases |
B. decreases but does not become zero |
C. remains same |
D. becomes zero |
40. One projectile moving with velocity V in space, gets burst into 2 parts of masses in the ratio 1:2. The smaller part becomes stationary. What is the velocity of the other part ? |
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A. 4V |
B. V |
C. 4V/3 |
D. 2V/3 |
41. A thief steals a box of weight W & jumps from the third floor of a building. During jump, he experiences a weight of |
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A. W |
B. 3W |
C. 1.5W |
D. zero |
42. Two electron beams are moving parallel in space but in opposite directions; then |
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A. they will attract each other |
B. they will repel each other |
C. no interaction will take place |
D. none of these |
43. Two wires with resistances R and 3R are connected in parallel, the ratio of heat generated in 2R and R is |
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A. 1 : 3 |
B. 2 : 1 |
C. 1 : 4 |
D. 4 : 1 |
44. A wire is drawn such that its radius changes from r to 2r, the new resistance is |
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A. 2 times |
B. 4 times |
C. 8 times |
D. 1/16 times |
45. In solids, inter-atomic forces are |
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A. totally repulsive |
B. totally attractive |
C. combination of (a) and (b) |
D. none of these |
46. When horse starts running all of a sudden, the rider on the horse back falls backward because |
A. he is taken aback |
B. he is afraid |
C. due to inertia of rest, the upper part of his body remains at rest |
D. due to inertia of motion, the lower part of his body comes in motion |
47. What should be the minimum velocity at the highest point of a body tied to a string, so that the string just does not slack ? |
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A. Ö (Rg) |
B. Ö (5Rg) |
C. (R/g)3/2 |
D. Ö (2Rg) |
48. If a person standing on a rotating disc stretches out his hands, the speed will: |
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A. increase |
B. decrease |
C. remain same |
D. none of these |
49. EMF is most closely related to |
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A. mechanical force |
B. potential difference |
C. electric field |
D. magnetic field |
50. Planetary system in the solar system describes |
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A. conservation of energy |
B. conservation of linear momentum |
C. conservation of angular momentum |
D. none of these |
51. Lenz's law is based upon |
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A. energy |
B. momentum |
C. angular momentum |
D. inertia |
52. Faraday's second law states that mass deposited on the electrode is directly proportional to |
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A. atomic mass |
B. atomic mass x velocity |
C. atomic mass/valency |
D. valency |
53. Unit of power is |
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A. kilowatt hour |
B. kilowatt per hour |
C. kilowatt |
D. erg |
54. Power can be expressed as |
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A. F.v |
B. 1/2 (Fv2) |
C. F.t |
D. F x v |
55. Units of coefficient of viscosity are |
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A. Nms-1 |
B. Nm2 s-1 |
C. Nm-2 s |
D. Nms-2 |
56. Dimensions of torque are |
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A. MLT-2 |
B. ML2T-2 |
C. M2L2T-2 |
D. ML-2T-2 |
57. A body of weight mg is hanging on a string, which extends its length by l. The work done in extending the string is |
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A. mg l |
B. mg l/2 |
C. 2 mg l |
D. none of these |
58. The water droplets in free fall are spherical due to |
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A. gravity |
B. viscosity |
C. surface tension |
D. inter-molecular attraction |
59. A ball of mass 1Kg is accelerating at a rate of 1ms-2. The rate of change of momentum is |
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A. 1 Kg ms-2 |
B. 2 Kg ms-2 |
C. 3 Kg ms-2 |
D. 4 Kg ms-2 |
60. A body orbitting around earth at a mean radius which is two times as great as the parking orbit of a satellite. The period of the body is |
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A. 4 days |
B. 2Ö 2 days |
C. 16 days |
D. 64 days |
61. Gamma rays are |
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A. high energy electrons |
B. low energy electrons |
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C. high energy electro-magnetic waves D. high energy positrons
PHYSICS
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