enwaecphysics2013

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1. The rising of a liquid in an open ended glass tube of narrow bore is Osmosis Adhesion Capillarity Surface tension 2. Which of the following units is equivalent to the Watt? Kgms-2 Kgm2s-3 Kgm2s-2 Kgm2s-2 3. Which of the following statements about pressure is correct? The pressure in a liquid increases with depth The higher the density of a liquid, the lower the pressure it exerts Pressure in a liquid acts only in a direction perpendicular to the sides of the containing vessel Pressure is independent of the acceleration due to gravity 4. A block of wood of mass 5kg is pulled on a platform by a force of 40N as illustrated in the diagram above. If the frictional force F, experienced by the block is 12N, calculate the magnitude of the acceleration of the block. 2.4ms-2 5.6ms-2 8.0ms-2 10.4ms-2 5. Solid friction, like viscosity, is Independent of surface areas in contact Independent of the relative motion between the layers Dependent on normal reaction In opposition to motion 6. The slope of a linear distance-time graph represents Acceleration Displacement Speed Velocity 7. A body of mass 2kg is released from rest on a smooth plane inclined at an angle of 60° to the horizontal. Calculate the acceleration of the body down the plane. [g=10ms-2] 3.1ms-2 5.2ms-2 6.0ms-2 8.7ms-2 8. The total area under a force-velocity graph represents Energy Momentum Power Pressure Use the following information to answer questions 9 and 10. A body of mass 20g projected vertically upwards in vacuum returns to the point of projection after 1.2s. [g=10ms-2] 9. Calculate the speed of projection 0.6ms-2 1.2ms-2 6.0ms-2 12.0ms-2 10. Determine the potential energy of the body at the maximum height of its motion. 0.36J 0.72J 360.00J 720.00J

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11. Four co-planar forces of magnitudes 10N, 17N, 6N, and 20N act at a point O as shown in the diagram above. Determine the magnitude of the resultant force. 53.0N 21.0N 7.0N 5.0N 12. The maximum displacement on either side of the equilibrium position of an object in simple harmonic motion represents Period Amplitude Wavelength Frequency 13. From Newton’s first law of motion, A body can only undergo translational motion Once a body remains at rest no force acts on it The net force acting on a body in uniform linear motion is zero A body’s inertia is its weight 14. A body of mass 11kg is suspended from a ceiling by an aluminium wire of length 2m and diameter 2mm. Calculate the elastic energy stored in the wire. [Young’s modulus of aluminium is 7.0 ×1010Nm-2 g=10ms-2, π=3.14] 1.1×10-1J 5.5×10-2J 1.1×10-4J 5.5×10-5J 15. The velocity ratio of an inclined plane Increases with increase in the angle of inclination Increases with decrease in the angle of inclination Decreases with decrease in the angle of inclination Is independent of the angle of inclination 16. Which of the following types of thermometers is used for the calibration of other thermometers? Liquid-in-glass thermometer Constant volume gas thermometer Optical thermometer Thermocouple 17. The magnitude of the expansion or contraction of a substance depends on the Temperature change Nature of the substance Size of the substance Which of the statements above are correct? I and II only II and III only I and III only I, II and III. 18. Highly polished silvery surfaces are Poor absorbers and poor emitters of radiation Poor absorbers and good emitters of radiation Good absorbers but poor emitters of radiation Poor absorbers but good emitters of radiation 19. The volume of a given mass of gas at 27℃ and 800mmHg is 76cm3. Calculate its volume at s.t.p. 100cm3 72.8cm3 60.0cm3 36.4cm3 20. The outlet of a bicycle pump is used to inflate a football as illustrated in the diagram above. Why does the pressure of the air inside the pump increases as the pump handle is slowly pushed downward at constant temperature? Momentum of the air molecules are increased Volume occupied by the molecules are increased Frequency of collision of the air molecules with the walls of the pump is increased More air molecules are colliding with one another in the system

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21. Ice of mass 10g at -5℃ was completely converted to water at 10℃. Calculate the quantity of heat used. [Specific heat capacity of ice=2.1Jg-1K-1 specific latent fusion of ice =336Jg-1] 105J 3255J 3465J 16821J 22. An electric heater has a resistance of 50Ω. When it is immersed in water and connected to mains source, it draws a current of 4.0A. Calculate the heat gained by the water if the heater is switched on for 2 minutes, assuming no heat losses to the surroundings. 400J 1600J 24000J 96000J 23. When salt is dissolved in water, the freezing point of the water Increases Decreases Remains the same Increases and later decreases 24. The diagram above illustrates a waveform. Which of the points on the waveform are in phase? P and R R and T P and T Q and S 25. The equation of a certain progressive transverse wave is y = 2sin 2π(t/0.01-x/30), where x and y are in cm and t in seconds. Calculate the period of the wave. 0.001s 0.010s 10.000s 100.000s 26. At which position should an object be placed in front of a concave mirror in order to obtain an image which is of the same size as the object? At the centre of the curvature At the principal focus Between the pole and the principal focus Between the centre of the curvature and principal focus 27. Images formed by a convex mirror are always Magnified Behind the mirror Real Inverted 28. The refractive index of a material is 1.5. Calculate the critical angle at the glass-air interface. 19° 21° 39° 42° 29. A diverging lens of focal length 30cm produces an image 20cm from the lens. Determine the object distance. 10cm 12cm 50cm 60cm 30. Which of the following statements about the Galilean telescope is not correct? The final image is inverted It is shorter than terrestrial telescope The final image is erect It has a small field of view

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31. Which of the following radiations has its frequency lower than that of infra-red radiation? Ultra-violet rays Gamma rays X-rays Radio waves 32. A string under tension produces a note of frequency 14Hz. Determine the frequency when the tension is quadrupled. 14Hz 18Hz 28Hz 56Hz 33. Which of the following statements about waves in pipes is correct? For open pipes, there is only one end correction to be accounted for For closed pipes, there are two end corrections to be accounted for Only odd harmonics are possible in closed pipes All harmonics are possible in closed pipes 34. When a person holds a negatively charged metal rod and stands bare-footed on the ground, how will the charges leak? Negative charges flows to the ground through the person’s body Positive charges flow from the ground through his body to neutralize the negative charges Positive charges in the air neutralizes the negative charges the person is holding Negative charges will leak through the air 35. A charge of 2.0 × 10-5C experiences a force of 80N in a uniform electric field. Calculate the magnitude of the electric field intensity. 8.0×106NC-1 4.0×106NC-1 4.0×104NC-1 2.0×104NC-1 36. An electric circuit is connected as illustrated above. Determine the equivalent emf and current flowing through the circuit respectively, neglecting the internal resistance of the cells. 2V, 1.0A 2V, 4.0A 6V,0.3A 6V, 3.0A 37. A potential difference of 12V is applied across the ends of a 6Ω resistor for 10 minutes. Determine the quantity of heat generated 720J 1200J 14400J 43200J 38. A galvanometer of internal resistance of 10Ω has a full scale deflection with a current of 10mA. Calculate the magnitude of the resistance required to convert it to a voltmeter capable of measuring up to 3V? 290Ω 300Ω 333Ω 1000Ω 39. Which of the following instruments is used to determine the accurate value of the electromotive force of a cell? Voltmeter Meterbridge Voltameter Potentiometer 40. The direction of motion of a current-carrying conductor placed within the opposite poles of a magnet is determined using Fleming’s left-hand rule Fleming’s right-hand rule Maxwell’s corkscrew rule Ampere’s rule

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41. Two straight current-carrying conductor are placed near each other. Which of the following diagrams correctly illustrates the magnetic field pattern formed by the conductors? 42. The capacitance of parallel plates capacitors varies Inversely as the square of the distance between the plates Directly as the square of the distance between the plates Inversely as the distance between the plates Directly as the distance between the plates 43. Which of the following devices works on the principle of electromagnetic induction? Carbon microphone Electric heater Moving iron ammeter Simple d.c. motor 44. Which of the following devices does not make sue of eddy current for its action? A/An Galvanometer Speedometer Induction furnace Induction coil 45. A coil of inductance 0.12H and resistance 4Ω, is connected across a 240V, 50Hz supply. Calculate the current through it. [π=3.14] 6.3A 33.3A 37.2A 40.0A 46. The work function of a metal is 2.56×10-19J. Calculate the frequency of a photon whose energy is required to eject from the metal an electron with kinetic energy of 3.0 eV. [1eV=1.6×10-19J h=6.6×10-34Js] 5.56×1019Hz 1.66×1019Hz 1.12×1015Hz 8.42×1014Hz 47. The minimum energy required to cause photo-electric emission when the surface of a metal is irradiated with electromagnetic radiation of suitable frequency is called Critical energy Ionization energy Work function Planck’s constant 48. Which of the following particles are termed nucleons in a neutral atom? Protons and neutrons Neutrons and electrons Protons and electrons Protons, electrons and neutrons 49. Which of the following statements about the use of radioisotopes is not correct? They are used to Induce mutations in plants and animals to obtain new and improved varieties Trace the paths of metabolic processes in plants and animals Estimate the age of rocks Locate broken bones 50. Which of the following phenomena supports the theory that waves have a particle nature? Electron diffraction Photoelectric effect Diffraction of light X-ray interference

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