JAMB UTME - Physics - 1981

A transformer has 300 turns of wire in the primary coil and 30 turns in the secondary coil.If the input voltage is 100 volts, the output voltage is

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When a ray of light passes from water to glass, it is

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The resistance of an open series circuit is

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a balloon inflated with helium gas at ground level is released. As it rises through a constant temperature atmosphere.

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The effect of closing the key K in the circuit shown above would be to

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The quantity (timbre) of sound depends on

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A body of mass 6kg rests on an inclined plane. The normal reaction is R and the limiting frictional force is F as shown in the image above. if F = 30N, and g = 10ms² then the angle of inclination \( \theta \) is

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When fixed mass of an ideal gas expands at constant temperature, which property of the gas molecule increases?

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in a light experiment with a convex lens a student plotted a graph as shown above of the reciprocal of object distance (1)/u against the reciprocal of image distance (1)/v . the focal length of the lens is given as

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A closed coil of wire is placed near a magnet. The magnet lies along the axis of the coil. Under which of the following conditions would there be no current in the coil?

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A liquid-in-glass thermometer should quickly register temperature changes. This is achieved by choosing a liquid that

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A vapour is said to be saturated when

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The latent heat of fusion of a substance is the heat required to

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Which of the following is NOT directly associated with direct current (DC)?

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The driver in a motor car, of which the total mass is 800kg and which is traveling at 20ms^-1, suddenly observes a stationary dog in his path 50m ahead. If the car brakes can exert a force of 2000N, what will most likely happen?

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If a source of sound is moving, a stationary listener will hear a sound of different frequency. This is called

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Which of the following is NOT an effect that can be produced by an electric current?

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Which of the following statements is applicable to a real image formed by a concave mirror? i. it can be observed on a screen ii. it is always inverted and in front of the mirror iii. it only seams to exist IV. it is formed by the actual converging of rays of light

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The principle of transmissibility of pressure in a fluid at rest in all directions is known as

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Which of the following does NOT describe the image formed by a plane mirror?

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An example of a scalar quantity is

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Which of the following elements are real magnetic materials?

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An object placed on the principle axis of a convex lens of focal length 10m produces a real image of double magnification. The image distance from the lens is

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Heat was supplied to a block of ice at 0^oC until half of it melted. Which of the following statements is true?

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Which type of radiation does not NOT originate within the nucleus?

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A body falls freely under gravity (g = 9.8ms^-2) from a height of 40m on to the top of a platform 0.8m above the ground. Its velocity on reaching the platform is

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Heat may be transferred by conduction, convection and radiation. By which of these methods does heat travel through vacuum?

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A solid weighs 4.8g in air, 2.8g in water and 3.2g in kerosine. The ratio of density of the solid to that of the kerosine is

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The wave motion above has a frequency

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If I is the current passing through a metallic resistor and H is the rate of Heat generated in the resistor at a constant temperature, then

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Change of state is accompanied by change of

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The relationship between the period T and the length T of a smile pendulum is T = 2\( \pi \) \( ( \frac{I}{g}) ^{ \frac{1}{2} } \). From experiment data of T and I, one can obtain the following graphs, i. T vs.I ii. T vs I² iii. T² vs. I iv. T vs \( \sqrt{I} \) v. logT vs logI. Which of the following graphs, are linear?

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Alternating current can induce voltage because it has a

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The extension in a spring when 5g wt was hung from it was 0.56cm. If Hooke's law is obeyed, What is the extension caused by a load of 20g wt?

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The resistance of a 240V, 60 watt electric filament bulb is

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An aircraft travelled from calabar to kano as follows: it flew first to ilorin convering a distance of 300km, 30^o west of North, and then flew 400km, 60^o East of North to kano. What is the resultant displacement?

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Which type of radiation does not NOT originate within the nucleus?

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Two particles X and Y starting from rest cover the same distance. The acceleration of X is twice that of Y. the ratio of the time taken by X to that taken by Y is

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All of the following frequencies are overtones of 320 Hz EXCEPT

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The mass of a proton is approximately equal to that of

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The absolute refractive indices of glass and water are \(\frac{3}{2}\) and \(\frac{4}{3}\) respectively. The refractive index at the interface when a ray travels from water to glass is

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The ice and steam points of mercury-in-glass thermometer of centigrade scale and of uniform bore correspond respectively to 3cm and 19cm lengths of the mercury thread when the length is 12cm, the temperature is

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An inclined plane of angle \(\theta\), acting as a simple machine, has a velocity ratio

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The following types of waves are transverse EXCEPT

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The lack of power of accommodation which is mainly due to the hardening of the eye lens and is usual with onset of old age is called?

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A cell of e.m.f 2V and internal resistance 1\(\Omega\) supplies a current of 0.5 amps to a resistance whose value is

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Which of the following statements is CORRECT?

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