Question

A student is doing an experiment to determine the effects of temperature on an object. He writes down that the initial temperature of the object was –3.5 ºK. Identify two errors in the student’s recorded temperature.

Answer 1

The student's recorded temperature of -3.5 ºK contains two errors - the use of negative value and the use of degree symbol with Kelvin.

Step-by-step explanation:

The two errors in the student's recorded temperature are:

1. The student recorded the temperature as -3.5 ºK. However, Kelvin (K) temperature scale does not have negative values. The absolute zero on the Kelvin scale is 0 K, which is the lowest temperature possible. Therefore, the recorded temperature should be 3.5 K instead.
2. The student used the degree symbol (º) while recording the temperature in Kelvin. The degree symbol is used to represent temperature in Celsius or Fahrenheit scales, not in Kelvin. Therefore, the correct way to write the temperature in Kelvin is 3.5 K, without the degree symbol.

Secondly, the Kelvin scale does not use the symbol º (degree), as it is an absolute scale. Temperatures in Kelvin are simply denoted as 'K' without the degree symbol.

Answer 2

1) The Kelvin temperature cannot be negative

2) The Kelvin degree is written as K, not ºK

Step-by-step explanation:

The temperature of an object can be written using different temperature scales.

The two most important scales are:

- Celsius scale: the Celsius degree is indicated with ºC. It is based on the freezing point of water (placed at 0ºC) and the boiling point of water (100ºC).

- Kelvin scale: the Kelvin is indicated with K. it is based on the concept of "absolute zero" temperature, which is the temperature at which matter stops moving, and it is placed at zero Kelvin (0 K), so this scale cannot have negative temperatures, since 0 K is the lowest possible temperature.

The expression to convert from Celsius degrees to Kelvin is:

`T(K)=T(^(\circ)C)+273.15`

Therefore in this problem, since the student reported a temperature of -3.5 ºK, the errors done are:

1) The Kelvin temperature cannot be negative

2) The Kelvin degree is written as K, not ºK