The temperature of a place on one sunny day is 113 in Fahrenheit scale. The Kelvin scale reading of this temperature will be
- A.318 K
- B.45 K
- C.62·8 K
- D.335·8 K
Correct answer
Explanation
The correct answer is A, 318 K. A reading of 113 on the Fahrenheit scale works out to 45 degrees Celsius, and adding 273 to that gives about 318 K. Fahrenheit is turned into Celsius with the relation C = (F - 32) x 5/9, so (113 - 32) x 5/9 = 81 x 5/9 = 45 degrees Celsius. The Kelvin scale begins at absolute zero and its degree is the same size as the Celsius degree, so K = C + 273.15, which makes 45 degrees Celsius equal to 318.15 K, written as 318 K in the options. Keep in mind that 0 degrees Celsius is 273 K, and that water freezes at 32 F and boils at 212 F. B is wrong because 45 is the Celsius value and not the Kelvin value. C is wrong because that figure comes from an incomplete conversion instead of the full formula. D is wrong because it adds 273 to the wrong Celsius value. Exam tip: do it in two steps, Fahrenheit to Celsius first, then add 273.
Practice Questions
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- A.Galileo
- B.Martin Luther
- C.Johannes Kepler
- D.Copernicus
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- C.Urea is produced from digestion of starch.
- D.Urea is produced in lung and kidney.
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- B.Objective lens-Condenser-Body tube-Eyepiece
- C.Condenser-Objective lens-Body tube-Eyepiece
- D.Eyepiece-Objective lens-Body tube-Mirror
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- D.Haemoglobin is only used for blood clotting and not for carrying gases.
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- B.Histones are proteins that are present in nucleus in association with DNA.
- C.Histones are proteins associated with lipids in the cytosol.
- D.Histones are proteins associated with carbohydrates in the cytosol.
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