Test: Celsius and Fahrenheit Scales - EmSAT Achieve MCQ

• Celsius scale was introduced by Andres Celsius. 
• In Celsius, scale water is taken as the base and certain standard values are set with respect to water, for example, the boiling point of water is 100 degrees Celsius and the melting point is 0 degrees Celsius.
• The Fahrenheit scale was introduced by Daniel Gabriel Fahrenheit. 
• According to this scale, the boiling point of water is taken as 212 degrees Fahrenheit and the melting point as 32 degrees Fahrenheit. This gives the exact difference of 180.

The relation between the Fahrenheit and Celsius scale is given by the equation.

Therefore, Celsius and Fahrenheit scales coincide at -40 degrees.

Given - Temperature (T_K) = 298 K
The relation between the Fahrenheit 'F' and kelvin 'K' temperature scales is given by

• Temperature: It is the measure of the degree of hotness and coldness of a body.
  • The SI unit of temperature is Kelvin (K).
• The various temperature scales commonly used are Celsius (C), Kelvin (K), Fahrenheit (F), and Rankine (Ra).
• Celsius: It has 100 degrees between the freezing and boiling points of water. 
  • Here 0° represents the freezing point and 100° represents the boiling point. In many countries, celsius is used to communicate day-to-day temperatures.
• Fahrenheit: The Fahrenheit scale was proposed by physicist Daniel Gabriel Fahrenheit in 1724. 
  • This scale is primarily used in the United States and some Caribbean countries to communicate day-to-day temperatures.

The temperature T in degrees Fahrenheit (°F) is equal to the temperature T in degrees Celsius (°C) times 9/5 plus 32:

Given C = F - 30
The relation between the °C and °F is given as,

⇒ 9(F - 30) = 5(F - 32)
⇒ 9F - 270 = 5F - 160
⇒ 4F = 110
⇒ F = 27.5
⇒ C = F - 30
⇒ C = 27.5 - 30
⇒ C = -2.5°C
Hence, option 2 is correct.

• Since the absolute zero temperature is 0 Kelvin. Below this temperature, we can't measure in kelvin scale.
• So the Kelvin scale of temperature is only positive. So option 3 is correct.

The freezing point and boiling point of water at different temperature scales are:
\

Since we need temperature in fahrenheit and celsius to be equal:

Now, let C = F = x

So, 
x = (x - 32) × 5/9
or, 9x = 5x – 160
or, 4x = -160
or, x = -40
Therefore, -40°C = -40°F

Given that:

Temperature (T) = 200 °C

Use the above-given formula:

Given, F = 32° Fahrenheit

• The relation between the Kelvin scale and Celsius scale is given by

⇒ K = 273.15 K

Given Δt_C = 5°C
We know that the relation between the Fahrenheit temperature (t_F) and the Celsius temperature (t_C) is given as,

Let the temperature at first is C₁ degree Celsius, and then it increased by 5° to C₂ degree Celsius, hence the difference between the initial and final temperature is given by
C₁ - C₂ = 5
Let the temperature is F₁ degree Fahrenheit corresponding to C₁ degree Celsius and F₂ degree Fahrenheit
When the temperature in degrees Celsius changed to C₂ which can be calculated from the formula.

Then the difference in temperature in degrees Fahrenheit equal to

At absolute zero, K = 0°