Tag: heat - measurement

Quizzes (5) Questions (94)

Questions Related to heat - measurement

Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

Which of the following is not true about Laboratory thermometers ?

  1. Laboratory thermometers are used to measure temperatures with a high degree of precision.

  2. Laboratory thermometers are used to measure body temperature.

  3. Range of laboratory thermometer is -10C to 110C

  4. Laboratory thermometers are designed for lab purposes such as checking boiling point, freezing point etc.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A laboratory thermometer is a tool used in laboratories to measure temperature with high accuracy. It can be partially or fully immersed in the substance being measured. A laboratory thermometer is recognizable by its long stem with a silver bulb at the end. The silver color in the bulb normally indicates the presence of mercury. Mercury expands as the temperature increases, thus raising the reading, while decreasing temperatures contract the mercury, lowering the reading. Mercury-in-glass thermometers are less used in the 21st century as preference is shifted to other types of thermometers, such as digital, alcohol-filled and organic-based thermometers.

hence,Laboratory thermometers are $not$ used to measure body temperature.

Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

Which of the following is the range of temperature recorded by a laboratory thermometer ?

  1. $0^oC$ to $100^oC$

  2. $-10^oC$ to $110^oC$

  3. $30^oC$ to $120^oC$

  4. $45^oC$ to $145^oC$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A laboratory thermometer is used for measuring temperatures other than the human body temperature. It ranges from -10˚C to 110˚C. Laboratory thermometers are designed for lab purposes such as checking boiling point, freezing point, or temperature of other substances

Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

Choose the correct answer from the alternatives given :
For measuring very high temperature, we use

  1. Mercury thermometer

  2. Thermoelectric pyrometer

  3. Platinum resistance thermometer

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Thermoelectric pyrometer is an instrument which uses one or more thermocouples to measure high temperature . 

Hence, option B is correct.

Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

If a thermometer reads freezing point of water as $20^{\circ}C$ and boiling point at $150^{\circ}C$ how much thermometer read when the actual temperature is $60^{\circ}C$.

  1. $98^{\circ}C$

  2. $110^{\circ}C$

  3. $40^{\circ}C$

  4. $60^{\circ}C$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
We let the unknown degree scale be called ${x}^{\circ}$
Now we know that the freezing point$={20}^{\circ}x$
The boiling point$={150}^{\circ}x$
This also means that ${20}^{\circ}x= {0}^{\circ}$ C($\because$ on a Celcius Scale, the freezing point is ${0}^{\circ}$)
And ${150}^{\circ}x={100}^{\circ}$C (On a  Celcius Scale, boiling point is ${100}^{\circ}$)
Also ${(150-20)}^{\circ}x= {100}^{\circ}$C ($\because$ on a Celcius Scale ${100}^{\circ}-{0}^{\circ}={100}^{\circ}$)
So, if ${100}^{\circ}$C$={130}^{\circ}x$
Then ${1}^{\circ}$C$={1.3}^{\circ}x$
To go from $C$ degree  to $x$, we need to use:
$x=1.3C+20$  
And $C=\dfrac{(x-20)}{1.3}$
So if the temperature given is ${60}^{\circ}$C, then we calculate $x$ as:
$C=\dfrac{(x-20)}{1.3}$  
$\Rightarrow 60=\dfrac{(X-20)}{1.3}$  
$\Rightarrow 60\times 1.3=x-20$  
$\Rightarrow 78=x-20$  
$\Rightarrow x= {98}^{\circ}$  
So ${60}^{\circ}$C will be equal to ${98}^{\circ}$ 
Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

The freezing point on a thermometer is marked as  $ 20^o$ and the boiling point as $150^o$. A temperature of $(60^o C)$on this thermometer will be read as:

  1. $40^o$

  2. $65^o$

  3. $98^o$

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$\begin{array}{l} By\, \, u\sin  g\, the\, \, formula \ \dfrac { { { T _{ t } }-{ T _{ fP } } } }{ { { T _{ BP } }-{ T _{ fp } } } } =\dfrac { { T-0 } }{ { 100-0 } }  \ \dfrac { { { T _{ t } }-20 } }{ { 150-20 } } =\dfrac { { 60 } }{ { 100 } }  \ { T _{ t } }-20=\dfrac { { 60\times 130 } }{ { 100 } }  \ { T _{ t } }=78+20 \ ={ 98^{ \circ  } } \ Hence,\, the\, option\, C\, \, is\, the\, correct\, answer. \end{array}\ $

Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

At low temperatures ................. type of thermometer is used.

  1. mercury thermometer

  2. water thermometer

  3. alcohol thermometer

  4. thermometers cannot be used
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Alcohol thermometer.
Alcohol expands uniformly.

It has a low freezing point (-115 degree centigrade) therefore it is very suitable for the place where the temperature gets very low.
It is an easily available cheap liquid, which is safe to use.
Alcohol is cheaper than mercury, and if you break the thermometer, it is not toxic.

Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

The boiling point of mercury is 367$^o$C. A mercury thermometer can be used to measure a temperature of 500$^o$C;

  1. by filling the space above mercury with oxygen at high pressure

  2. by filling the space above mercury with nitrogen at low pressure

  3. by filling the space above mercury with nitrogen at high pressure

  4. by keeping the space above mercury as vacuum
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The mercury thermometer can be used above its boiling point by filling up the space above mercury with nitrogen at high pressure because as pressure increases, boiling point also increases.