enwaecphysics2015

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1. Which of the following statements about mass and weight are correct? Weight is the force of gravity on a body The mass of a body is the quantity of matter in the body The weight of a body is greatest at the equator The mass of a body is greatest at the poles A. I and II only B. I and III only C. II and IV only D. III and IV only 2. Materials that can be stretched and still return to their original forms when stresses are removed are said to be Elastic Elastomer Plastic Thermoplastic 3. Which of the following units is derived? Kg M K N 4. The barometer reading at a place is 73.5cm Hg. Calculate the pressure at a point 30m below the surface of water contained in a reservoir at the place. [g=10ms-2, density of mercury=1.3 × 104 kg m-3, density of water= 1.0 × 103 kg m-3 ] 4.0 ×105Nm-2 3.0 ×105Nm-2 2.0 ×105Nm-2 1.0 ×105Nm-2 5. An object floats in a fluid when it displaces its Volume of fluid in which it floats Mass of fluid in which it floats Weight of fluid in which it floats Density of fluid in which it floats 6. The resultant force in a couple is Zero Infinite The sum of the forces The product of the forces 7. The slope of a straight-line-velocity-time graph represents Uniform acceleration Uniform speed Total distance travelled Work done 8. A body is projected with an initial velocity u at an angle θ to the horizontal. The time taken by it to reach its maximum height is given by the expression 2usinθ/g (u2 sin2 θ)/2g usinθ/g (usin θ)/2g 9. Which of the following statements describes a body in a stable equilibrium correctly? A person walking on a tight rope Ball on a smooth horizontal table Ball resting on an inverted hemispherical bowl Ball in the middle of a hemispherical bowl 10. In a school compound, a girl walks 40 m due east from the laboratory to the staff room to submit her report. Then she turns and walks 30m due north to her classroom. Determine the magnitude of her displacement from the laboratory. 10m 35m 50m 70m

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11. Two strings each inclined at an angle of 300 to the horizontal are used to hold a bucket of water weighing 20 N. Calculate the tension in each string. 20√3 N 20 N 10√3N 10N 12. A bullet fired vertically upwards reaches a height of 500m. Neglecting air resistance, calculate the magnitude of the initial velocity of the bullet. [g=10ms-2] 500.0ms-1 100.0ms-1 70.0 ms-1 50.0 ms-1 13. A uniform bar AB is balanced on a knife-edge which 60cm from B by a mass of 22 g which hangs at C 10cm from A as illustrated in the diagram above. Calculate the mass of the bar. 133.2g 66.0g 60.0g 22.0g 14. A body of mass 1000 kg is released from a height of 10m above the ground. Determine its kinetic energy just before it strikes the ground. [g= 10 ms-2] 10 J 103J 104J 105 J 15. The diagram below illustrates four test-tubes containing the same volume of a liquid at different pressures. In which of the test tubes does the liquid boil last if they are supplied with the same quantity of heat? 16. The crackling noise produced by aluminium roofing sheets on a house during a hot sunny day is as a result of Thermal equilibrium of the sheets Conduction of heat by the sheets Contraction of the sheets Expansion of the sheets 17. Water is unsuitable for use as a thermometric liquid because it Expands unevenly between 00C and 40C Has a narrow temperature range Has a concave meniscus Maintains a fixed density 18. The diagram above illustrates a block and tackle pulley system in which an effort E supports a load of 100.0 N. If the efficiency of the machine is 75%, calculate the value of E. 22.2 N 38.0 N 67.0 N 75.0 N 19. A quantity of hot water at 1000C is added to 400g of water at 100C until the temperature of the mixture is 600C. Calculate the mass of the hot water added. [Specific heat capacity of water =4200 jkg-1 K] 200g 320g 400g 500g 20. In an experiment in which a molten substance is allowed to cool, the cooling curve shown above was obtained. The temperature 600C is known as the Vaporization point Cooling temperature Boiling point Melting point

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21. Which of the following heat concept is a method of heat transfer that does not require a material medium? Conduction Radiation Diffusion Convention 22. Which of the following unit is the S. I. unit of heat capacity? J kg-1 J kg-1k-1 J kg-1 J kg-1k-1 23. The pressure applied to an enclosed fluid at one end is transmitted equally is transmitted throughout the fluid and to the container walls. This statement is Archimede’s principle Bernoulli’s principle Pascal’s principle Heisenberg’s uncertainty principle 24. The diagram above illustrates a wave form. Determine the speed of the wave. 5.4 ms-1 8.4 ms-1 9.6 ms-1 10.0 ms-1 25. What type of wave is emitted by a loud speaker? Transverse Longitudinal Gamma Radio 26. An object is placed 15cm from a diverging lens of focal length 12cm,the image of the object formed by the lens is Real and 6.67cm from the lens Virtual and 6.67cm from the lens Real and 60.0cm from the lens virtual and 60.00cm from the lens 27. Which of the following types of eye lenses is suitable for correcting the eye defect illustrated by the ray diagram above? Bi-converging Bi-diverging Plano diverging Diverging meniscus 28. A swimming pool is 2.1m deep. If it contains water of refractive index of 1.3m, Calculate the apparent depth of the pool. 3.4m 2.7m 1.6m 0.8m 29. When an air column is set into vibrations, the distance between two consecutive nodes of the resultant wave is One-quarter of the wave length One-half of the wave length The wave length Twice the wave length 30. A girl standing from the foot of a cliff claps her hand and hears the echo 1.8s later. Calculate her distance from the cliff,[Speed of sound in air =320ms-1] 82m 102m 128m 140m

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31. Red light travels faster than blue light when both of them pass through a glass prism because the Refractive index of red light is greater than that of blue light Refractive index of blue is greater than that of blue light Red light is more intense than the blue light Blue light is more intense than the red light 32. An object is placed 20cm from a concave mirror of focal length 15cm.calculate the linear magnification of the image formed. 0.5 1.5 2.0 3.0 33. All electromagnetic wave in a vacuum have the same Wave length Frequency Speed Amplitude 34. The diagram above illustrates two charged particles w and x .The charges on w and x are respectively negative: negative negative: positive positive: positive positive: negative 35. An alternating current supply is connected to an electric lamp which lights with the same brightness as does with the direct current source e.m.f 6 V. The peak potential difference of a.c supply is 4.6V 6.0V 8.5V 12.0V 36. An electric generator rated 12 kw, 2 kv distributes a power through a cable of resistance 20Ω.calculate the power loss in the cable. 120w 360w 720w 2400w 37. Which of the following statement is correct? When capacity of different values are connected in series The same charge flows through them The same voltage appears across each capacitor Different quantities of charges flow through them with different voltage across them Different quantities of charges flow through them with same voltage across them. 38. Which of the following statement (s) about three- pin plugs is/are correct? The brown wire is the life wire The fuse is connected to the live wire The earth wire is connected blue I only II only I and II only I, II and III 39. The symbol illustrated above is that of a resistor Which absorbs light Which emits light Which absorbs heat to function properly Whose resistance is light dependent 40. A wire of cross- sectional area of 0.60mm2 has a resistivity of 7.2×10-7 Ω m. Calculate the length of the wire that will have a resistance of 3 Ω. 0.25m 2.50m 3.60m 36.00m

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41. A battery of emf 24V is connected to three resistors P, Q, and R as illustrated in the diagram above. Determine the voltage across resistor Q. 5V 10V 14V 24V 42. The mass of the earth is 6.0 × 1024 kg and that of the moon is 7.0 ×1022 kg. If the distance between them is 4.0 × 108 m, calculate the force of attraction between. [G=6.7 ×10 -11 Nm2 kg-2]. 1.8 × 105N 1.8 × 106N 1.8 × 1015 N 1.8 ×1020N 43. The angle which the direction of the earth magnetic field makes with the horizontal at a place is known as Angle of contact Angle of dip Angle of declination Magnetic meridian 44. What must be connected between the points P and Q to establish a steady current through the incomplete circuit diagram illustrated above? Fuse Ammeter Cell Voltmeter 45. When current flows through a moving-coil galvanometer, the force exerted on the pointer depends on the Strength of the current Magnetic field strength Length of the coil Which of the statement(s) above is/are correct? I only II only I and III only I, II and III 46. In a nuclear fission process, the mass defect was 1.2 ×10-5kg. Calculate the energy released. [Speed of light in vacuum=c= 3.0 ×108ms-1] 1.08 ×1011 J 5.20 × 1011 J 1.08 × 1012 J 2.50×1013J 47. Which of the following statements about a diode is correct? Reverse bias diodes have low resistance Forward bias diodes produce high resistance Forward bias diodes produce high current Forward bias diodes function as a result of heat 48. Which of the following phenomena best supports the wave nature of matter? Electron diffraction Photoelectric effect Electron momentum Black body radiation 49. Which of the following radiations constitutes a stream of electorns? Gamma rays X-rays Cathode rays Radio waves 50. (_88^226)Ra emits two alpha particles to produce Polonium (Po) nuclide. The correct formula for the nuclide is (_86^224)Po (_86^222)Po (_84^222)Po (_84^218)Po

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