Which of the following statements are correct about an object in equilibrium under parallel forces? i. the total clockwise moments of the forces about any point equals the total anti-clockwise moments about the same poin…
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1990
A particle of mass M which is at rest splits up into two. If the mass and velocity of one of the particles are m and v respectively, calculate the velocity of the second particle
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1990
A car moving with a speed of 90kmh-1 was brought uniformly to rest by the application of the brakes in 10s. How far did the car travel after the brakes were applied?
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1990
Which of the following is a fundamental unit?
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1990
What is the length of liquid column in a barometer tube that would support an atmospheric pressure of 102000Nm-2 if the density of the liquid is 2600kgm-3? [g = 10ms-2]
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1990
An inclined plane which makes an angle of 30o with the horizontal has a velocity ratio of
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1990
A body of mass 10kg rests on a rough inclined plane whose angle of tilt \(\theta\) is variable. \(\theta\) is gradually increased until the body starts to slide down the plane at 30o. The coefficient of limiting friction…
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1990
A stone of mass m kg is held h meters above the floor for 50s. The work done in joules over this period is
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1990
To keep a vehicle moving at a constant speed v, requires power P, from the engine. The force provided by the engine is
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1990
1kg of copper is transferred quickly from boiling water to a block of ice. Calculate the mass of ice melted, neglecting heat loss. [specific heat capacity of copper 400Jkg-1K-1 and latent heat of fusion of ice 333 x 103J…
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1990
The pressure of a gas when cooled at constant volume will decrease because the molecules
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1990
A bar of initial length /0 is heated through a temperature change \(\Delta\)t to a new length I. The linear expansivity, a, of the bar is
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1990
The resistances of platinum wire at the ice and steam points are 0.75 ohm and 1.05 ohm respectively. Determine the temperature at which the resistance of the wire is 0.90 ohm
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1990
40m3 of liquid is mixed with 60m3 of another liquid Q. If the density of P and Q are 1.00kgm-3 and 1.6kgm-3 respectively, what is the density of the mixture?
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1990
Shadows and eclipses result from the
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1990
A wave disturbance travelling in air enters a medium in which its velocity is less than that in air. Which of the following statements is true about the wave medium?
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1990
A light wave of frequency 5 x 1014Hz moves through water which has a refractive index of \(\frac{4}{3}\). Calculate the wavelength in water if the velocity of light in air is 3 x 108ms-1
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1990
Which of the following statements? i. land and sea breezes are natural convection currents. ii. convection may occur in liquids or gasses but not in solids. iii. the vacuum in a thermos flask prevents heat loss due to co…
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1990
Which of the following conditions will make water boil at a temperature of 100oC when the atmospheric pressure is 750mmHg?
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1990
When light is incident on an object which is magenta in colour, which of the following colour would be absorbed?