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

Suppose in a clinical thermometer, the difference between first and second bigger marks is $1^o$ and there are 5 small divisions between them then each small division refers to the difference in scale of:

  1. $0.1^oC$
  2. $0.2^oC$
  3. $0.3^oC$
  4. $0.4^oC$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Suppose in a clinical thermometer, the difference between first and second bigger marks is 1o and there are 5 small divisions .
the bigger marks read one degree and there are five divisions between them. Then, one small division can read $\dfrac{1}{5} =  0.2 ^oC$ 

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

What is the limit of temperatures human body can achieve?

  1. $25^oC$ to $42^oC$
  2. $35^oC$ to $42^oC$
  3. $35^oC$ to $62^oC$
  4. $5^oC$ to $42^oC$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Normal human body temperature, also known as normothermia or euthermia, is the typical temperature range found in humans. The normal human body temperature range is typically stated as $36.5–37.5 °C (97.7–99.5 °F).$
The limit of temperatures human body can achieve is $35^oC $ to $62^oC$

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

Which of the following methods would reduce the temperature of hot tea

  1. Add more tea at the same temperature

  2. Add water at the same temperature

  3. Add water at temperature lower than the temperature of tea

  4. Add water at temperature higher than the temperature of tea
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

temperature of hot tea add water at temperature lower than the temperature of tea

Water is an  effective coolant,For a coolant a substance has to have a high specific heat capacity, meaning it can absorb a lot of heat. It also has to be nontoxic, or non-poisonous. It also needs to be fairly common, which would mean since it is readily available, the cost should be fairly low

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

One litre of water at $30^{o}C$ is mixed with one litre of water at $50^{o}C$. The temperature of the mixture will be

  1. 80C

  2. more than 50C but less than 80C

  3. 20C

  4. between 30C and 50C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Let the first volume of water be V1. Let the second volume of water be V2. Let the initial temperature of the first volume of water be θ1. Let the initial temperature of the second volume of water be θ2.

Let the energy required to heat a unit volume of water by unit temperature by C.

So, if the final temperature is θfinal, we have

heat gained by the first volume of water

$=V _1×C×(θ _{final}−θ _1)$

and

heat lost by the second volume of water

$=V _2×C×(θ _2−θ _{final}).$

By the law of conservation of energy,

heat lost = heat gained

∴$V _1×C×(θ _{final}−θ _1)=V _2×C×(θ _2−θ _{final})$

∴$V _1θ _{final}−V _1θ _1=V _2θ _2−V _2θ _{final}$

∴$θ _{final}=V _1θ _1+V _2θ _2V _1+V _2$

Substituting the given values,

$θ _{final}=\dfrac{30+50}{2}=40^∘C$.

The answer is option D
Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

Human body temperature is well measured by 

  1. A clinical thermometer

  2. A laboratory thermometer

  3. Thermostat

  4. Both A & B can be used
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A clinical thermometer is a thermometer used to measure human body temperature. Most old ones use mercury thermometer. It is accurate and sensitive, because it has a narrow place where the mercury level rises very fast.

These thermometers are used in clinics by doctors, so they are also called a doctor's thermometers or medical thermometers. Most of them show both Celsius scale and Fahrenheit temperature scales. The scale runs from 35 degree Celsius to 42 degree Celsius.

Medical thermometers are cleaned before and after each use, with alcohol.

It has a kink which does not allow the mercury level to fall on its own.
Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

A laboratory thermometer is dipped in a beaker containing hot water. As the thermometer is removed the mercury level will

  1. rise

  2. fall

  3. it may rise or fall depending upon how much water is kept inside the beaker

  4. neither rise nor fall
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A laboratory thermometer is dipped in a beaker containing hot water. As the thermometer is removed the mercury level will fall.

As the temperature of hot water is much higher than the room temperature th level of mercury rises but when it is removed then the thermometer comes down as the temperature of room is less than the temperature of hot water hence level will fall

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

Choose the correct option

  1. Temperature of a water kept inside a beaker is measured when the laboratory thermometer is held inside the water

  2. Temperature of a water kept inside a beaker is measured when the laboratory thermometer is removed from the water

  3. Temperature of our body is measured when the clinical thermometer is kept inside the mouth

  4. Temperature of our body is measured when the clinical thermometer is removed from the mouth
Reveal answer Fill a bubble to check yourself
A,D Correct answer
Explanation
A.Temperature of a water kept inside a beaker is measured when the laboratory thermometer is held inside the water.This gives accurately the temperature of water in beaker.
B
Temperature of a water kept inside a beaker is measured when the laboratory thermometer is removed from the water.This method is wrong as thermometer reading will be drop as it removed from the beaker.Hence this will give error in reading.
C
Temperature of our body is measured when the clinical thermometer is kept inside the mouth.In the clinical thermometers the maximum temperature is first allowed to reach then we remove the thermometer and  take the reading.Hence temperature inside mouth gives error in reading 
D
Temperature of our body is measured when the clinical thermometer is removed from the mouth.In the clinical thermometers the maximum temperature is first allowed to reach then we remove the thermometer and  take the reading.Hence this method is correct.
Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

A clinical thermometer can not be used to measure

  1. Room temperature

  2. Human body temperature

  3. Temperature of a boiling water

  4. Temperature of a lake water
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
clinical Thermometer (or doctor's thermometer) is used for measuring a person's temperature. 
The temperature range that is marked on a clinical thermometer is about $35^oC$ to $43^oC$ (or $ 95^oF$ to $109^oF). $
After a clinical thermometer has been used to record a patient's temperature, the mercury is prevented from contracting into the glass bulb by the constriction kink.
Hence cannot be used to measure temperature of boiling water which is about $100^oC$
Multiple choice physics heat - measurement thermometers application of various thermometric scales different types of thermometers

How should a thermometer be dipped inside beaker containing water

  1. Vertically

  2. Tilted

  3. Any of the above way

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

A thermometer is a device that measures temperature or a temperature gradient. A thermometer has two important elements: (1) a temperature sensor (e.g. the bulb of a mercury-in-glass thermometer or the digital sensor in an infrared thermometer) in which some change occurs with a change in temperature, and  2.some means of converting this change into a numerical value (e.g. the visible scale that is marked on a mercury-in-glass thermometer or the digital readout on an infrared model). Thermometers are widely used in industry to monitor processes, in meteorology, in medicine, and in scientific research.thermometer be dipped inside beaker containing water vertically

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

Choose the correct option 

  1. A clinical thermometer should be washed using water before and after use

  2. A clinical thermometer should be washed using antiseptic solution before and after use

  3. A clinical thermometer can be used after it is heated by fire

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A clinical thermometer is a thermometer used to measure human body temperature. Most old ones use mercury thermometer. It is accurate and sensitive, because it has a narrow place where the mercury level rises very fast.

These thermometers are used in clinics by doctors, so they are also called a doctor's thermometers or medical thermometers. Most of them show both Celsius scale and Fahrenheit temperature scales. The scale runs from 35 degree Celsius to 42 degree Celsius.

Medical thermometers are cleaned before and after each use, with alcohol.

It has a kink which does not allow the mercury level to fall on its own.