enwaecphysics2016

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The dimensions of momentum are? MLT B. ML-1T C. MLT-1 D. ML-1T A student measures the volume of a liquid using a measuring cylinder. What else needs to be measured by the student in order to determine the density of the liquid? Depth of the liquid in the cylinder Mass of the cylinder Mass of the liquid Temperature of the liquid. ` The diagram above represents the graph of stress against strain for an elastic wire. The point Q on the graph is the? Elastic Limit B. Breaking Point C. Yield Point D. Proportional Limit A ball dropped from the op of a tower, Due to air resistance, it reaches the terminal velocity. Which of the following statements about its motion is/are correct? The acceleration of the ball is Zero The net force on the ball is zero The velocity of the ball increases I only B. I and II only C. II and III only D. I, II and III Which of the following substances lowers the surface tension of water? Metal B. Sand C. Detergent D. Paper An object volume 400cm3 and density 2.5cm3 is suspended from a spring balance with half its volume immersed in water. Determine the reading on the spring balance. (Density of water = 1g cm-3). A. 1200g B. 1000 C. 800g D. 400g F/N The diagram above illustrates a force-distance graph for the motion of a wooden block. Determine the done on the block when moved through a distance of 5m. 4 J B. 15 J C. 25 J D. 100 J The two positions of a body undergoing a uniformly acceleration motion are (10s, 10ms-1) and (30s, 50ms-1) on the velocity-time graph. Calculate the magnitude of the acceleration of the body. 0.5ms-2 B. 2.0ms-2 C. 10.0ms-2 D. 40.0ms-2 At a birthday party, the celebrant pops a corked fruit wine. If the cork shoots out of the bottle at an angle of 400 to the horizontal and travels a horizontal distance of 4.50m in 1.25s, calculate the initial speed of the cork. 4.2ms-1 B. 4.7ms-1 C. 5.6ms-1 D. 7.1ms-1 A uniform meter rule is balanced on a fulcrum placed at the 35cm mark by suspending a mass of 120kg at the 10cm, mark. Calculate the mass of the meter rule. 60g B. 80g C. 150g 200g

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A plank is placed along the path on which a wheel barrow containing send is pushed at a construction site to prevent it from sticking as illustrated in the diagram above. The large area of the plank prevents wheel borrow from getting stuck by. Increasing the reaction Increasing the pressure Decreasing the pressure on the ground Decreasing the weight on the ground. When a body is thrown vertically upwards, its velocity at the maximum height is. Maximum B. Zero C. Double its initial value D. Half its initial value Resonance occurs when one vibrating object causes a second object to vibrate at its own natural. Amplitude B. Speed C. Frequency D. Intensity The mouth piece of a telephone handsets converts. Electrical energy to sound energy Sound energy to electrical energy Sound energy to radio wave Radio wave to sound energy. Four identical trolleys are loaded with different masses and move along a straight road at the same speed. Which of the trolleys has the greatest inertia? In the clinical thermometer, the function of the kink is to. Prevent the back flow of mercury after use Ensure the back flow of mercury after use Maintain the thermometer property of mercury Allowed the temperature attained to be read I only B. I and II only C. I and IV D. III and IV only. Which of the following statement correctly defines the boiling point of a liquid? The temperature at which the. Saturated vapor pressure equals the atmospheric pressure Molecules leaves the liquid at a rate equal to the rate at which they return Molecules leaves the liquid at a rate higher than that at which they return Molecules leave the liquid at a rate lower than the rate at which they return. The diagram above is used to determine the Boiling point of water. B Atmospheric pressure. C. Upper fixed point of a thermometer. D. Amount of water in the atmosphere. An aluminum rod of length 1.8cm at 100C is heated to produce a difference in length of 0.007m. Calculate the temperature to which it is heated. (Linear expansivity of aluminum = 2.3 x 10-5 x 10 K-1 ) 1550C B. 1600C C. 1690C D. 1790C A mercury-in-glass thermometer read 4cm at ice point and 29cm at steam point. Calculate the temperature when the mercury level is at 9cm. 130C B. 200C C. 330C D. 380C

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The continuous stirring in the method of mixtures to determine the specific thermal capacity of a substance ensures. Continuous dissipation of heat to the room Uniform distribution of thermal energy to all parts of the mixture The thermal energy is confined to the mixture That there is rapid het exchange. Which of the following statement is correct about water? The freezing point is lowered The freezing point is increased There is no exchange in freezing The change in the freezing point depends on the temperature of the surrounding. A pressurized perfume bottle is left on the window pane of a room. What happens to the gas molecules of the perfume on a sunny day? They. Expand B. Collide less often C. Move more rapidly D. Contract. Given that v,fand λ are velocity, frequency and wavelength of a wave respectively. Which of the following equations is correct? A.v= f^2λ B.f= V/λ C. f= V/λ^2 D.λ= f/λ^2 Three letters are placed in front of a plane mirror as illustrate in the diagram below. The imaged is illustrated by. J EJ B. J EL C. J E J D. LE J The distance between two successive troughs of a wave is 0.4m. If the frequency of the source is 825Hz, calculate the speed of the wave. 165.0 ms-1 B. 300.0 ms-1 C. 412.5 ms-1 D. 825.0ms-1 X-ray and infra-rays are both electromagnetic which Common Property do the waves have? Both waves. Are longitudinal B. Have the same frequency. C. Have the same wavelength. D. Travel at the same speed in a vacuum The image formed by a concave mirror is real, inverted and magnified, when the object is placed. At the focus. B. At the centre of curvature. Beyond the centre of curvature. D. Between the centre of curvature and focus. Total internal reflection Is a phenomenon of refraction of light Occurs when light rays travel into a denser medium Occurs when the critical angle is just exceeded Is a phenomenon of reflection of light Which of the statement above are correct? I and II only B. I and III only C. I, II and III only D. I, III and IV only Complementary colors are those which. Have the same reflection wave Have the same wave length Add-up to produce black light Add-up to produce white light.

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The diagram above illustrates the waveform of a note produced by vibrations in an air column length L. if the speed of sound in air is V derive an expression for the frequency of the note. V/L B. 5VL/2 C. 5L/4V D. 5V/VL The pair of musical instruments that works on the vibration of air in pipes is? Piano and the organ. B. Guitar and the Flute. C. Trumpet and the Violin. D. Flute and Trumpet. An astronomical telescope has objective and eye-piece lenses of focal length 3.5m and 5cm respectively. Determine the magnifying power of the telescope when in normal adjustment? 70.0 B. 17.5 C. 7.0 D. 0.7 An aluminum cable of diameter 4 x 10-3 m and resistivity 3.0 x 10-8Ω m has a resistance of 21 Ω. Calculate the length of the cable. (π=3.14). 8.0 x 102m B. 8.8 x 103m C. 8.0 x 104m D. 8.8 x 104m. The ammeter A2 shown in the circuit diagram above reads 3.0 A. Determine the reading of the ammeter a. 12A B. 9A C. 7A D. 2A The electricity meter in houses measure energy units consumed in? Kilowatt. B. Volt C. ampere D. Coulomb A man and his friend have masses 70kg and 60 kg respectively. If they are seated 1.0m apart. Calculate the gravitational force of attraction between them.(G = 6.67 x 10-11 Nm2 kg-2). 1.69 x 10-14N B. 2.80 x 10-7N C. 1.30 x 102N D. 6.30 x 1013N The p.d. across a parallel-plate capacitor is 102 V, if the distance between the plates is 10cm calculate the magnitude of the electric field strength between the plates. 1.5 x 104Vm-1 B. 1.0 x 105Vm-1 C. 1.5 X 105Vm-1 D. 2.0 x 105Vm-1 Two different material s. rubbed against each other, acquire opposite charges when separated. This is an example of charging by? Induction B. Friction C. Conduction D. Convection. Which of the following is factor does not affect the E.M.F of a primary cell? Size B. Internal resistance. C. Operating Temperature D. Duration of usage.

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Two magnets are used to magnetize a soft iron bar PQ as illustrated in the diagram above. The correct polarity P and Q respectively are? S And N B. N and S C. S and S D. N and N In storing magnets, keepers are used to? Reduce self-demagnetization Cancel the effect of the earth’s magnetic field Protect the magnet from stray electric fields Increases the strength of the magnets. A 10μC charge moves with a velocity of 1.0 x 105ms-1 at right angle to a uniform magnetic field of flux density 5.0 x 10-4T. Calculate the force on the charge. 5.0 x 11-5 N B. 5.0 x 10-4 N C. 5.0 x 105 N D. 5.0 x 10-6N Which of the following statements is he not correct about steel and soft iron? Steel is more readily magnetized than soft iron. Permanent magnets are usually made of steel Soft iron is more readily magnetism than steel Soft iron more readily loses its magnetism than steel. What determines the polarity at the ends of an electromagnet? The. Magnitude of the current passing through the wire. Material of the core of the magnet Material of the coil Direction of current in the wire How many beta particles are emitted in the radioactive decay of(_80^( 198))Au→(_80^198)Hg? 1 B. 2 C. 3 D. 5 The phenomenon by which two light atomic nuclei combine to form a heavy nuclide with the release of energy is known as? Radioactivity B. Nuclear Fusion C. Nuclear Fission D. Chain Reaction. Which of the following graph is correct for the decay of radioactive substance with a half-life of 2 years? In a p-type semiconductor, the Number of holes are equal to the number of electrons Electrical resistivity increases. Electrons are the majority charge carries Holes are the majority charge carries. Let ∆x be the uncertainly in the measurement of position and ∆pthe uncertainly in measurement of momentum. Then the uncertainly principle relation is given as ∆x.∆P> =h B.∆x .∆P≤=h C. ∆x .∆p ≥=h D.∆x .∆p≥h

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