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Pergunta 1 Relatório
A machine has an efficiency of 80%. If the machine is required to overcome a load of 60N with a force of 40N, calculate its velocity ratio.
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Pergunta 2 Relatório
A constant force of 5N acts for 5s on a mass of 5kg initially at rest. Calculate the final momentum of the mass.
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Pergunta 3 Relatório
Which of the following properties is NOT exhibited by sound waves?
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Pergunta 4 Relatório
The space surrounding a magnet in which the magnetic force is exerted is
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Pergunta 5 Relatório
The area under the curve of a velocity time graph represents
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Pergunta 6 Relatório
A stone is released from a height of 80m above the ground. Calculate its velocity just before it strikes the ground. (g=10ms-2)
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Pergunta 7 Relatório
The resistance of a series R-C circuit is 5 ω If the impedance of the circuit is 13 ω calculate the reactance of the capacitor
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Pergunta 9 Relatório
Calculate the amount of heat generated in an external load of resistance 8Ω if an alternating current of peak value 5 A is passed through it for 100s.
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Pergunta 10 Relatório
Which of the following scientists postulated that moving particles exhibit wave properties?
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Pergunta 11 Relatório
A short chain is usually attached to the rear side of petro tanker trailing behind it to ensure that the
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Pergunta 12 Relatório
For which of the following sets are the units fundamental?
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Pergunta 13 Relatório
\(^{226}_{88}Ra\) \(\to\) \(^{222}_{866}Rn\) + X + Energy. The equation above represents a nuclear decay of radium isotope. What is X?
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Pergunta 15 Relatório
Evaporation of a liquid produces cooling of the liquid because the
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Pergunta 17 Relatório
Which of the following motions will be produced by a pair of equal, opposite and non-collinear parallel forces acting on a body?
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Pergunta 19 Relatório
A sheet of white paper viewed through blue glass appears blue because
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Pergunta 20 Relatório
A platinum-resistance thermometer has a resistance of 4Ω at 0°C and 12Ω at 100°C. Assuming that the resistance changes uniformly with temperature. Calculate the resistance of the thermometer when the temperature is 45°C.
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Pergunta 21 Relatório
The mode of transference of heat which does not require any material medium is
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Pergunta 22 Relatório
Young’s modulus of elasticity is the ratio of stress to strain, provided the load does not exceed the
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Pergunta 23 Relatório
In 90 seconds, the mass of a radioactive element reduces to \(\frac{1}{16}\) of its original value. Determine the half- life of the element.
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Pergunta 25 Relatório
Calculate the critical angle for light travelling from water to air. (Refractive index of water = 1.33)
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Pergunta 26 Relatório
A wire of length 100cm and cross-sectional area 2.0 × 10-3cm2 has a resistance of 0.10 ω. Calculate its electrical conductively.
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Pergunta 28 Relatório
Which of the following statements about the concept of solid friction is NOT true?
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Pergunta 29 Relatório
An object is placed 30 cm in front of a concave mirror of focal length 20cm. Calculate the distance between the object and the image.
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Pergunta 30 Relatório
A transformer is required to give 120V from a 240V mains supply. If the primary has 5500 turns, how many turns has the secondary?
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Pergunta 31 Relatório
Which of the following instruments can be used to measure e.m.f. most accurately.
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Pergunta 32 Relatório
Which of the following radiations have the longest wavelength?
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Pergunta 33 Relatório
Which of the following statement(s) is/are correct about the isotopes of an elements? They have the same
I. chemical properties
II. nucleon number
III proton number
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Pergunta 34 Relatório
A ball of mass m moving at velocity u collides with another ball of equal mass at rest. If the two balls move off together after the impact, calculate their common velocity.
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Pergunta 35 Relatório
Lines of force
I. Begin and end on equal and opposite electric charges.
II. are in state of tension which causes them to shorten
III. attract one another.
Which of the statement(s) is/are correct?
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Pergunta 37 Relatório
A body is launched from the earth’s surface, of radius R, so that it just escapes from the gravitational influence of the earth; If the gravitational constant is G and the mass of the earth is M, what is the escape velocity of the boby.
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Pergunta 38 Relatório
The inability of the eye to focus near objects is known as
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Pergunta 39 Relatório
The volume of a given mass of gas is 40cm3 at 27° C. What is its volume at 90° C if its pressure remains constant?
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Pergunta 40 Relatório
Two equal capacitances are connected first in series and then in parallel. The ratio of the effective series capacitance to the effective parallel capacitance is
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Pergunta 41 Relatório
Which of the following statement(s) is/are correct?
I. When a liquid expands its density falls
II. When a mercury-in-glass thermometer is placed in a hot liquid, the mercury level first descends and then rises.
III. The apparent expansion of a liquid is greater than its real expansion.
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Pergunta 42 Relatório
The distance between two successive crests of a water wave is 0.5m. If a particle on the surface of the water wave makes two complete vertical oscillations in 1s, calculate the speed of the wave.
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Pergunta 43 Relatório
How much heat is required to convert 50g of water at 100°C to steam at the same temperature? (Specific latent heat of vaporization of water = 2260 Jg-11)
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Pergunta 44 Relatório
A narrow, uniform glass tube, closed at one end, constains air which is sealed by a thread of mercury. The tube is placed first horizontally and then vertically with the open end at the top. Which of the following statements is correct?
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Pergunta 45 Relatório
Water in an open container boils at a lower temperature when heated at the top of a mountain than at sea-level because at the top of a mountain
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