(B)The triple point of a substance is unique, i.e. it occurs at one particular set of values of pressure and temperature. The melting point of ice and boiling point of water are not unique. They change with change in value of pressure or due to the presence of impurities in water.

The thermometer is a device that measures temperature. Its graduation is done in $$^{\circ}C$$ or Fahrenheits.

$$^\circ C$$

The correct answer is option (c). The normal human body temperature is $$37^{o}C$$.

 False

Explanation:

• Radiation heat transfer is the technique of transferring heat from one body at higher temperature to another body at lower temperature without affecting the medium.

• Transfer of heat by radiation does not need any material medium. 

• The sun's heat, for example, is transmitted to the earth by radiation.

Correct answer:  (iii) upwards

Explanation:

• Heat is always transferred vertically upwards through convection. 

• This occurs because medium particles close to a heat source absorb heat from the source and begin to move faster, so they become farther i.e. the medium expands. 

• As a result, the density of medium near the source of heat becomes less i.e. it becomes lighter. 

• The less dense medium rises up and the dense medium from above moves down to take its place.

• Thus, a current is set up in the medium which is called a convection current.

The velocity of heat radiation in the vacuum is $$equal$$ to that of light. 

The layers if the atmosphere are heated through Radiation from sun and convection currents, are responsible for heating.

The polished surface reflects all the radiation. And a thermos flask is used to keep the heat out so the well-polished surface reflects all radiation from outside.

In winter, the temperature of the surrounding is low compared to the body temperature $$37.4 ^\circ C$$ . Since woollen clothes are bad conductors of heat, so they keep the body warm .

To mark $$0^o\,C$$ on thermometer, we need to put it in where temperature is  $$0^o \,C$$

We cannot always rely on our sense of touch to decide whether an object
is hot or cold. Sometimes it may deceive us, thus the given statement is false.

Among the above options, Ice is colder because it exists at zero or below zero degrees Celcius. 

Temperature is measured by a device called thermometer, thus option $$C$$ is correct.

A reliable measure of the
hotness of an object is its
temperature thus option $$A$$ is correct.

India has adopted the celsius scale, thus option $$B$$ is correct.

Clinical thermometer cannot be used to measure high temperatures.Range of Clinical Thermometer is 35°C to 42°C. Thus the given statement is false.

Different types of thermometers
are used for different purposes for example, to measure human body temperature a clinical thermometer is used however the maximum and minimum
temperatures of the previous
day, reported in weather
reports, are measured by
a thermometer called the
maximum -minimum thermometer thus the given statement is wrong.

Digital thermometers are another way of measuring the human body temperature which do not use mercury as it is a toxic substance. Thus the given statement is correct.

let us assume initial Temperature $$T_1=T$$ then final will be

$$T_2=\dfrac{50}{100}T+T=\dfrac{150}{100}T=\dfrac{15}{10}T$$

energy radiated

$$e_1=\sigma A T_1^4\quad \left(1\right)$$

$$e_2=\sigma A T_2^4\quad \left(2\right)$$

$$\%$$ increase in radiation

$$=\dfrac{e_2-e_1}{e_1}\times 100$$

$$=\dfrac{\sigma A T_2^4-\sigma A T_1^4}{\sigma A T_1^4}\times 100$$

$$\dfrac{\left(\dfrac{15}{10}T\right)^4-T^4}{T^4}\times 100$$

$$\dfrac{15^4-10^4}{10^4}\times 10^2$$

$$\dfrac{50625-10000}{10^2}$$

$$=406.25$$

$$\approx 400\%$$

Hence $$(d)$$ option is correct.

The image (I) and (III) are the clinical thermometers that are used to measure the body temperature only.

The temperature recorded by the dry bulb thermometer will be greater. Due to evaporation cooling is caused which lowers the temperature of the bulb wrapped in a wet hanky. 

Temperature is measured in Kelvin or Degree celsius hence options A and B are correct.