Tag: heat - measurement

Questions Related to heat - measurement

Boiling water can be measured by 

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

  1. Clinical thermometer

  2. Laboratory thermometer

  3. Both may be used conveniently

  4. Both of them can not be used

Show answer
Correct Option: B
Explanation:
Laboratory thermometers are used to measure temperatures or temperature changes with a high degree of precision. That's why these are mainly used in laboratories. For exp : To measure boiling points of solutions, water etc. They are made up of glass and strength through thermal tempering or annealing. Types : liquid-in-glass, bimetallic strip, infrared based thermometer.
Hence, the answer is Laboratory thermometer.

A clinical thermometer reads temperature from

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

  1. $35^oC to \ 42^oC$

  2. $0^oC to \ 100^oC$

  3. $25^oC to \ 42^oC$

  4. $35^oC to \ 62^oC$

Show answer
Correct Option: A
Explanation:
A clinical thermometer is a thermometer used to measure human body temperature. Most made in $20th$ century are mercury-in-glass thermometers. They are very sensitive as mercury level rises very fast with small variation in temperature most of these thermometers shows Celsius and Fahrenheit ( medical thermometer ) scales and runs from $35°C$ to $42°C.$
Hence, the answer is $35°C$ to $42°C.$

The clinical thermometer is designed to measure the temperature of

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

  1. Human body

  2. Bodies kept in refrigerators

  3. Room temperature

  4. boiling water

Show answer
Correct Option: A
Explanation:
A Clinical thermometer is a thermometer used to measure human body temperature. Most made in $20th$ century are mercury-in-glass thermometers. They are very fast with small variation in temperature. Most of these thermometers shows Celsius and Fahrenheit ( medical thermometer ) scales and runs from $35°C$ to $42°C.$
Hence, the answer is Human body.

What is the use of kink near the bulb in clinical thermometer

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

  1. It prevents the level of the mercury from falling when taken out of the mouth

  2. It allows the level of the mercury to fall when taken out of the mouth

  3. It allows the level of the mercury to rise when taken out of the mouth

  4. It prevents the level of the mercury from rising when taken out of the mouth

Show answer
Correct Option: A,B
Explanation:
Since, in clinical thermometer, mercury is used and level of mercury rises very rapidly with small variation in temperature that's why thermometers provided with kink near the bulb so it prevents the level of mercury from falling when taken out of mouth.
Hence, the answers are it prevent the level of the mercury from falling when taken out of the mouth, it allows the level of the mercury to fall when taken out of the mouth.

When a mercury thermometer is inserted in a pot of hot water and the reading is recorded , what temperature is being 

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

  1. Average temperature of water and surroundings

  2. Average temperature of thermometer

  3. Average temperature of water and thermometer

  4. Temperature difference between water and surroundings

Show answer
Correct Option: B
Explanation:

In this process, thermal equilibrium will eventually be reached after inserting the thermometer in hot pot. Hence heat is transferred from the water to the thermometer. 

The steam point and the ice point of a mercury thermometer are marked $80^0$ and $20^0.$  what will be the temperature in centigrade mercury scale when this thermometer reads $32^0$

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

  1. $20 ^ { 0 } \mathrm { C }$

  2. $5 ^ { 0 } \mathrm { C }$

  3. $10 ^ { 0 } \mathrm { C }$

  4. $26 ^ { 0 } \mathrm { C }$

Show answer
Correct Option: A
Explanation:

$(x-20)/(80-20) =(C-0)/(100-0)$
$(x-20)/60=(C-0)/100$

Now, given question$,$
$x=32 $
then$ ,$
$(32-20)/60=(C-0)/100$
$12/60=C/100$
$C=20^0$
hence in centigrade thermometer $20^0C$
Hence,
option $(A)$ is correct answer.

Mercury is often used in clinical thermometers. Which one of the following properties of mercury is not a reason for this ?

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

  1. The coefficient of the thermal expansion is large

  2. It is shiny

  3. It is a liquid at room temperature

  4. It has high density.

Show answer
Correct Option: D
Explanation:
Mercury is used in thermometer as it has high coefficient of  expansion so even the highest change can be observed, it is spiny So you can see the level of mercury clearly and it is liquid for a wide range of temperature.
Hence, OPTION : D (density).

150 g of ice is mixed with 100 g of water at temperature $80^oC$. The latent heat of ice is 80 ca/g and the specific heat of water is $1 cal/g-^oC$. Assuming no heat loss to the environment, the amount of ice which does not melt is

physics heat - measurement introduction to temperature application of various thermometric scales different types of thermometers

  1. 100 g

  2. 0 g

  3. 150 g

  4. 50 g

Show answer
Correct Option: D
Explanation:

Heat given by water $=100\times 1\times 800=8000 cal$
Heat taken by ice $=8000 cal=m\times 80$
$m=100 gm$
So amount of ice which does not melt $=150-100=50 gm$.

The following three objects (1) a metal tray, (2) a block of wood,and (3) a wooden cap are left in a closed room overnight. Next day the temperature of each is recorded as $T _1, T _2$ and $T _3$ respectively. The likely situation is 

physics heat - measurement introduction to temperature application of various thermometric scales different types of thermometers

  1. $ T _1 = T _2 = T _3 $

  2. $ T _3 > T _2 > T _1 $

  3. $ T _3 = T _2 > T _1 $

  4. $ T _3 > T _2 = T _1 $

Show answer
Correct Option: A
Explanation:

All three will be inthermal equilibrium with air of room. so temprature of the three will be same

A new temperature scale uses X as a unit of temperature, where the numerical value of the temperature t$ _x$ in this scale is related to the absolute temperature T by t$ _x$ = 3T + 300. If the specific heat of a material using this unit is 1400 J kg$^{-1}$ X${^-1}$ its specificne in the S.I. system of units is

physics heat - measurement introduction to temperature application of various thermometric scales different types of thermometers

  1. 4200 J kg$^{-1}$ K$^{-1}$

  2. 1400 J kg$^{-1}$ K$^{-1}$

  3. 466.7 J kg$^{-1}$ K$^{-1}$

  4. impossible to determine from the information provided

Show answer
Correct Option: A
Explanation:

$t _x = 3 T + 300                 Q = ms \Delta 0$
$\Delta t _x = 3 \Delta T$
$\displaystyle S = \frac{Q}{m \Delta \theta}                 S = \frac{Q}{m \Delta \theta}$
Since, unit of 8 is joule in both system
            X                                    T
$m = m _0 kg$                   $m _0 kg$
$Q = Q _0 J$                       $Q _0  J$
$\Delta t _x$                               $\Delta T$
$S _x = \displaystyle \frac{Q _0}{m _0 \Delta t _x} = 1400     S _r = \frac{Q _0}{m _0 \Delta T} = \frac{3 Q}{m _0 \Delta t _x}$
$S _r = 3 \times 1400 = 4200 J-kg^{-1} K^{-1}$