The change in temperature of a body is 50°C. The change in temperature on the…
2016
The change in temperature of a body is 50°C. The change in temperature on the Kelvin scale is
- A.
50 K
- B.
323 K
- C.
122 K
- D.
70 K
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Correct answer: A
The Celsius and Kelvin scales share the same size of one degree; they differ only in where the zero point is placed (0°C = 273.15 K). Because of this, a CHANGE (interval) in temperature has the same numerical value on both scales — unlike an absolute temperature reading, which does need the 273.15 offset added or subtracted: ΔT(K) = ΔT(°C).
The body's temperature changes by 50°C, so ΔT(°C) = 50.
Since intervals convert one-to-one between the two scales, ΔT(K) = ΔT(°C) = 50.
Hence the change on the Kelvin scale is 50 K.
This holds regardless of the starting point: if the initial temperature is T°C (equal to (T + 273.15) K), the final temperature is (T + 50)°C (equal to (T + 50 + 273.15) K). Subtracting the two Kelvin readings gives (T + 50 + 273.15) minus (T + 273.15) = 50 K — the offset cancels, confirming the interval is 50 K independent of T.