Superconductivity is a material property associated with
Answer: D
Superconductivity is the complete loss of electrical resistance that some materials show below a critical temperature.
A current started in a superconducting ring will circulate indefinitely without loss. The effect was discovered by Kamerlingh Onnes in mercury in 1911, at 4.2 K.
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The dynamo is a device for converting
Answer: B
A dynamo converts mechanical energy into electrical energy. A coil rotated in a magnetic field has a current induced in it, by Faraday's law of electromagnetic induction.
The reverse device, converting electrical energy into mechanical, is the electric motor.
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The branch of medical science which is concerned with the study of disease as it affects a community of people is called
Answer: A
Epidemiology studies disease as it affects populations - how often it occurs, in whom, where, and what determines its spread.
Pathology studies the changes disease causes in tissue, oncology deals with cancer, and palaeontology with fossils.
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Which of the following elements is a metal
Answer: D
Gallium (Ga) is the metal. It is a soft, silvery element of group 13 that melts at 29.8°C - low enough to liquefy in the hand.
Sulphur and iodine are non-metals; selenium is a non-metal usually classed with the metalloids.
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Which prefix is often used with scientific terms to indicate that something is the same, equal or constant?
Answer: A
The prefix iso- indicates sameness, equality or constancy, from the Greek isos, equal.
Hence isotherm (equal temperature), isobar (equal pressure), isotope (same place in the periodic table) and isomer (same formula). Mega- means large, meta- beyond or changed, and quasi- resembling.
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The use of which of the following devices has given the modern biologist a better insight into the internal structure of cells
Answer: B
The electron microscope revealed the internal structure of the cell. Using electrons instead of light, it resolves detail down to a fraction of a nanometre - a thousand times finer than a light microscope.
Mitochondria, the endoplasmic reticulum, ribosomes and the structure of membranes were all discovered with it.
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Pollination by birds is called
Answer: B
Pollination by birds is ornithophily, from the Greek ornis, bird.
Bird-pollinated flowers are typically large, red or orange, odourless and rich in nectar. Pollination by insects is entomophily, by wind anemophily, and autogamy is self-pollination within the same flower.
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The fastest-running terrestrial animal is
Answer: A
The cheetah is the fastest land animal, reaching about 110 km/h in short bursts of a few hundred metres.
Its flexible spine, non-retractable claws and enlarged heart and lungs are all adaptations for the sprint, but it overheats within about half a minute and must give up.
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A cyclone is an engineering device that is used to
Answer: B
A cyclone in engineering is a device that separates particles from a gas or liquid stream. The stream is spun in a conical vessel, and the heavier particles are thrown outward and fall to the bottom while the clean fluid leaves through the top.
Cyclones are widely used as dust collectors, having no moving parts and needing no filter medium.
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Cystitis is the infection of which of the following?
Answer: B
Cystitis is inflammation or infection of the urinary bladder, from the Greek kystis, bladder.
It is usually bacterial, most often E. coli from the bowel, and is far more common in women because the urethra is shorter.
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