enwaecphysics2014

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1. A ball falling through a viscous liquid is acted upon by Upthrust only Upthrust and the ball’s weight The ball’s weight and viscous force Upthrust, the ball’s weight and viscous force. 2. An object of mass m moves with a uniform speed v round a circular path of radius r. If its angular speed is ω, the magnitude of the centripetal force acting on it is mω2r (mv^2)/r Mωr (mv^2)/r^2 3. When an elastic material is stretched by force, the energy stored in it is Kinetic Potential Thermal Electrical 4. If no net force acts on an object, the object maintains a state of rest or constant speed in a straight line. The above is a statement of Newton’s First law of motion Second law of motion Third law of motion Law of universal gravitation 5. Which of the velocity-time graphs below correctly describes the motion of a body pulled by a force that is equal to the frictional force acting on it? 6. When the linear momentum of a body is constant, the net force acting on it Is zero Increases Decreases Remains constant 7. Which of the following pairs of physical quantities is made up of vectors? Speed and displacement Mass and force Displacement and acceleration Momentum and length 8. The knowledge of surface tension is applied in the following areas except in Manufacturing of rain coats Production of palm oil Floating of a needle on water Washing of plates with soapy water 9. A body is projected vertically upwards with a speed of 10ms-1 from a point of 2m above the ground. Calculate the total time taken for the body to reach the ground. [g=10ms-2]. 1.00s 2.00s 2.18s 3.00s 10. A car starts from rest and covers a distance of 40m in 10s. Calculate the magnitude of its acceleration. 0.25ms-2 0.80ms-2 3.20ms-2 4.00ms-2

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11. The diagram above illustrates a uniform metre rule is balanced on a pivot by some masses. Calculate the value of M. 500.0g 400.0g 44.4g 25.0g 12. The period of a simple pendulum X is 5s. What is the period of a simple pendulum Y which makes 50 vibrations in the same time it takes X to make 20 vibrations? 12.5s 2.5s 2.0s 1.2s 13. Alcohol of mass 21g and density 0.7g cm-3 is mixed with 10g of water. Determine the density of the mixture. [Density of water= 1.0 gcm-3] 0.775gcm-3 0.780gcm-3 0.875gcm-3 0.880gcm-3 14. A device that converts mechanical energy into electrical energy is A dynamo An electric motor An induction coil A transformer 15. The SI unit of power is N Pa W J 16. A screw-jack has the distance between its successive threads as P and the length of its tommy bar as r. Its velocity ratio is given by the expression (2πr^2)/P 2πr/P 2π/rP P/2πr 17. Heat transfer by conduction is similar to wave motion because There is increase in temperature Transfer of materials is involved Charged particles vibrate at right angles No transfer of materials is involved 18. The temperature at which the water vapour in the air saturates the air and begins to condense is known as Dew point Critical point Boiling point Triple point 19. The change of state from solid to liquid occurs at constant temperature when the temperature is lower than the boiling point when temperature is just near freezing point when temperature is equal to the boiling point 20. Which of the following types of thermometers can be used to measure a range of temperatures from -50℃ to 50℃? Clinical Mercury-in-glass Alcohol-in-glass I only II only III only I and II only

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21. A body of mass M kg rests on a plane inclined at an angle θ to the horizontal. The component of the weight of the body parallel to the plane is Mg sinθ Mg cosθ Mg tanθ Mg secθ 22. A quantity of water at 20℃ is mixed with another quantity of water at 70℃. The final steady temperature of the mixture is 40℃. Determine the ratio of the mass of the cold water to that of the hot water. 7:2 3:2 2:5 1:2 23. The mass of an empty density bottle is 30g. When filled with a liquid, the mass of the bottle and the liquid is 40g. On heating the filled bottle through 40℃, the mass reduces to 38Ig. Calculate the apparent cubic expansivity of the liquid. 6.25× 10K-1 6.25 × 10-3K-1 2.50 ×10-3K-1 2.50× 10-4 K-1 24. A car travelling at 30 m-1 overcomes a frictional resistance of 100N while moving. Calculate the power developed by the engine. [1hp=0.75 kW] 0.23hp 0.40hp 4.00hp 4.40hp 25. The quality of a note depends on its Frequency Pitch Overtones Amplitude 26. A transverse wave can be distinguished from a longitudinal wave by Diffraction Reflection Refraction Polarization 27. The superposition of waves to produce maximum or zero effect at a point is known as Reflection Refraction Interference Diffraction 28. Refraction of light differs from reflection in that, in refraction At least two media are involved There is a change in the direction of the ray The speed of the ray changes. Which of the statement(s) above is/are correct? I only I and II only II and III only I and III only 29. Which of the following relations about the focal length fo of the objective and the focal length fe of the eye piece of a compound microscope is correct? fo=fe fo< fe fo> fe fe=2fo 30. The functional difference between a lens and a mirror is that a lens reflects a beam of light while a mirror refracts it refracts a beam of light while a mirror reflects it absorbs incident rays while a mirror transmits them transmits incident rays while a mirror absorbs them

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31. The diagram above illustrates an electromagnetic wave travelling with a speed 3.0×108ms-1. Calculate the wave length of the wave. 0.05m 0.15m 0.16m 0.40m 32. An observer hears an echo 1.26 seconds after blowing a whistle near a cliff. Calculate the distance of the observer form the cliff. [Speed of sound in air= 330ms-1] 104.4m 207.9m 415.8m 523.8m 33. A fish inside a pond appears to be at a depth of 1.5m when viewed vertically from above. The refractive index of the water in the pond is 1.3. Calculate the apparent displacement of the fish. 2.50m 1.95m 1.50m 0.45m 34. An object is placed in front of two plane mirrors inclined at 60 °to each other. Determine the number of images formed. 2 3 5 7 35. An ammeter can be adapted to measure potential difference by using a Shunt Multiplier Rheostat Resistance box 36. The region around a magnet in which magnetic force can be experienced is known as Declination Flux density Field Flux 37. In an a.c. circuit, when the supply voltage frequency is equal to the resonant frequency, the current Leads the supply voltage by 90 ° Lags behind the supply voltage by 90 ° Leads the supply voltage by 45 ° is in phase with the supply voltage 38. The energy stored in a simple cell is electrical nuclear thermal chemical 39. Which of the following conditions occur at resonance in a series RLC circuit? Impedance equals resistance Current is maximum Reactances are maximum Current and voltage are 90 ° out of phase I and II only I and III only I, II and III only I, II, III and IV. 40. An electric motor converts Electrical energy to mechanical energy Mechanical energy to electrical energy Mechanical energy to sound energy Electrical energy to thermal energy

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41. A 15μF capacitor is connected to a 240V, 50Hz a.c source. Calculate the reactance of the capacitor [π=3.142] 16Ω 68Ω 106Ω 212Ω 42. Two identical charges situated 20cm apart in a vacuum repel each other with a force of 1.0N. Calculate the value of each charge. [14πεo)-1=9×109Nm2C-2] 2.1μC 3.6μC 4.0μC 4.4μC 43. In the circuit above, E is a battery of negligible internal resistance. If its emf is 9.0V, calculate the current in the circuit. 1.8A 1.0A 0.8A 0.3A 44. A wire of length 100cm has a resistance of 10Ω. If its cross-sectional area is 0.005cm2, determine its resistivity. 0.0005Ωcm 0.0015Ωcm 0.0016Ωcm 0.0700Ωcm 45. A transformer has 400 turns of wire in the primary coil and 40 turns in the secondary coil. If the input voltage is 150 volts, calculate the magnitude of the output voltage. 150V 55V 36V 15V 46. The circuit above illustrates a standard resistor R, voltage source E and a lamp L connected in the series. If the temperature of R is increased, the brightness of the lamp will Increase sharply Decrease slightly Remain the same Increase gradually 47. The energy required to separate the nucleus in an atom completely is known as Mass defect of the atom Electron binding energy Excitation energy Nuclear binding energy 48. Which of the following statements is the major disadvantage of nuclear fusion over nuclear fission? Nuclear fusion releases more energy More neutrons are released in fusion than in fission Fusion does not release as much dangerous radiation as fission Fusion reactions occur more readily than fission 49. An aluminium foil is placed across a beam of radioactive source. Which of the following types of radiation will be stopped by it? Alpha and beta particles Alpha and gamma particles Beta and gamma particles Gamma particles only 50. An element of nucleon number P and atomic number Q emits an alpha particle from its nucleus. The resultant numbers of the new element formed are respectively, P-4 and Q+2 P-4 and Q-2 P+2 and Q+2 P+2 and Q-2

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