4. Heat Class 7 Science Solutions English Medium-Assignment

Question - Answer:

Que: What is a clinical thermometer?

Ans: The thermemeter that is used to measure human body temperature is called a clinical thermometer.

Que2: How is degree celsius denoted?

Ans: ^oC.

Que3: What is the normal temperature of human body?

Ans: the normal temperature of human body is 37^oC.

Que4: what gets hotter soon, land or water?

Ans: Land.

Que5: What caution do you suggest regarding a clinical the thermometer?

Ans: A clinical thermometer should not be used for measuring the temperature of any object other than the human body. Also aoid keeping the thermometer in the sun or near a flame. It may break.

Que6: Why should you wear white clothes in summer and black clothes in winter?

Ans: Dark surface absorb more heat and, therefore, we'feel comfortable withe dark - coloured clothes in the winter. Light coloured clothes reflect most of heat the falls on them and, therefore, we feel more comfortable wearing them in the summer.

Que: Describe the construction of a clinical thermometer.

Ans: A clinical thermometer consists of a long, narrow, uniform glass tube. It has a bulb at one end. This bulb contains mercury. Outside the bulb, a small shining thread of mercury can be seen. There is also a celsius scale on the thermometer.

Que: While Construcating a house in a castal area, in which direction should the window preferbly face and why?

Ans: Window should preferably towards the sea beach so that the sea breeze coming form sea keeps the house cool during the day time.

Que: The mercury does noit fall or rise in a clinical thermometer when taken out of the mouth. Explain why?

Ans: Because of the kink present in the thermometer, the mercury does not fall or rise.

Que: It a pan ias removed from the fire, then why does it cool down?

Ans: When a pan is removed from tghe fire, it loses heat to the surroundings by radiation and its cools down.

Que: Name the mode of transfer of heat in which meadium is not required.

Ans: Radiation is the mode of transfer of heat in which is not required. 

Que: its is preferred to use thin blankets rather than one thick blanket. Explain the reason?

Ans: In case of two thin blanke5ts. there is an air gap which does not allow heat pass out frim the body and its is not as such as in case of one thick blanket.

Que: Why is it adivised not to hold the thermometer by its bulb while reading it?

Ans:  it adivised not to hold the termometer bulb while reading it as the level of mercury increases from the actual reading by our body temperature.

Que: Briefly mention one application of kink in the clical thermometer.

Ans: The clinical thermometer consists of kink which prevents the mercury level from falling on its own.

Que: explain how do we find out how hot an object really is.

Ans: by using thermometer, we can measure the degree of hotness of a body.

Que:How can we measure the temperature of other object rather than human body?

Ans: Temperature of other object is measured with laboratory thermometer because clinical thermometer is not suitable for higher temperture.

Que: How does the heat travel in air?

Ans: heat travels in air through convection.

Que: We are adivsed to use an umbrella when you go out in the sun. comment.

Ans: We use an umbrella to protect us from heat coming from the sun in the from of radiation.

Que: state the limitation of clinical thermomter.

Ans: The clinical thermometer cannot be used for measuring the temperature of any lobject more than 42^o C. If it kept in the sun or near a flame, then this clinical thermometer can be hbreak.

Que: Is the body temperature of every person 37^oC.

Ans: No, the body temperature of every person is not 37^oC. It is an average temperature. It could be slightly higher or slightly lower.

Que: While reading a clinical thermometer, what precautuions should we take?

Ans: Reading a clinical thermometer.

Que: The clinical thermometer is not used to measure high temperature. why?

Ans: Clinical thermometer has the rage 35o C to 42o C. If we use it to measure high temperature, it may braek and mercury present in the clinical thermometer is harmful. so, we cannot use clinical thermometer to measure high temperature.