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A student studies some equations. power = work / time force = mass × acceleration velocity = displacement / time How many vector quantities are contained in the equations? 1, 2, 3, 4
When a block of wood of mass 2 kg is pushed along the horizontal flat surface of a bench, the friction force is 4 N. When the block is pushed along the bench with a force of 10 N, it moves with a constant speed of 3 m / s., speed of 5 m / s., acceleration of 3 m / s2., acceleration of 5 m / s2.
How much energy would be released if 1 X 10 -20 kg of matter was entirely converted to energy? (The speed of light is 3 X 10 ^ 8 m/s) 3 x 10 ^ -12 J, 9 x 10 -7 J, 4.5 x 10 ^ -4 J, 9 x 10 ^ -4 J
What is a property of both liquids and gases? They always fill their containers., They are incompressible., They can flow., They have molecules
What conditions of temperature and surface area would produce the most rapid evaporation from a pool of water on a road surface? temperature high surface area large, temperature high surface area small, temperat
The sensitivity of a liquid-in-glass thermometer depends on the volume of liquid used and the diameter of the bore of the thermometer. Which changes will produce the greatest increase in sensitivity? volume of liquid decrease bore diameter decrease, volume of liquid decrease bore dia
The energy required to change liquid water into water vapour at the same temperature is called latent heat of vaporisation. What does this energy do? increases the average separation of the water molecules, increases the average speed of the water mo
A 2 kW kettle containing boiling water is placed on a balance. It is left there and continues to boil for 5 minutes. The balance reading changes by 0.2 kg. What does this information give as a value for the specific latent heat of vaporisation of water? 2000 J / kg, 3000 J / kg, 50 000 J / kg, 3 000 000 J / kg
The heat from the hot water in a metal radiator passes through the metal and then spreads around the room. What are the main processes by which the heat is transferred through the radiator and then spread around the room? through the metal radiator conduction through the metal conduction, through the metal radiat
What is meant by the term wavefront? the distance between successive peaks of a wave, the distance between the trough and the peak of a
The human eye has a converging lens system that produces an image at the back of the eye. An eye views a distant object. What type of image is produced? real, erect, same size, real, inverted, diminished, virtual, erect, diminished, virtual, inverted,
A wire has a resistance of 8 ?. A second wire, made of the same material, has half the length and twice the cross-sectional area. What is the resistance of the second wire? 1 ?, 2 ?, 8 ?, 16 ?
Which of the following would cost the least if operated from the same voltage supply? a 5000 W electric cooker used for 1 minute, a 1000 W electric fire used for 10 minutes, a 500 W el
A house-owner replaces a failed fuse for the lights of the house. When the lights are switched on, the second fuse also fails. The house-owner then uses a third fuse with a higher rating than the previous two. Why is this not a sensible thing to do? Fuses only allow the circuit to work if the rating is exactly right., The third fuse will melt becau
Why is electrical energy usually transmitted at high voltage? As little energy as possible is wasted in the transmission cables., The current in the transmission
A nucleus of sodium, Na, has 11 protons and 12 neutrons. Which symbol represents this nucleus? 11 / 12 Na, 12 /11 Na, 23 / 11 Na, 23 /12 Na
The half-life of a radioactive material is 24 years. The activity of a sample falls to a fraction of its initial value after 72 years. What is the fraction? 1 over 3, 1 over 4, 1 over 6, 1 over 8
Which is the correct comparison of the penetrating power and ionising power of alpha-particles and gamma radiation? greater penetrating power alpha greater ionising power alpha, greater penetrating power