Q38. When we come out in the sun, we feel warm. How does the heat from the sun reach us?

 

Q39. In summer we prefer light-coloured clothes and in winter we usually wear dark-coloured clothes. Why is it so?

 

Q40. What is sea breeze?

 

Q41. Two thin blankets joined together are usually warmer than one thick blanket. Give reason.

 

Q42. How water gets heated?

 

Q43. An iron ball at 40°C is dropped in a mug containing water at 40°C.

The heat will

(a) flow from iron ball to water.

(b) not flow from iron ball to water or from water to iron ball.

(c) flow from water to iron ball.

(d) increase the temperature of both.

 

Q44. A wooden spoon is dipped in a cup of ice cream. Its other end

(a) becomes cold by the process of conduction.

(b) becomes cold by the process of convection.

(c) becomes cold by the process of radiation.

(d) does not become cold.

 

Q45. Stainless steel pans are usually provided with copper bottoms. The reason for this could be that

(a) copper bottom makes the pan more durable.

(b) such pans appear colourful.

(c) copper is a better conductor of heat than the stainless steel.

(d) copper is easier to clean than the stainless steel.

 

Q46. State the similarities and differences between the laboratory thermometer and the clinical thermometer.

 

Q47. What are the precautions that need to be observed while reading a clinical thermometer?

 

Q48. State the precaution to be observed while using a laboratory thermometer.

 

Q49. Why can't we use a laboratory thermometer to measure human body temperature?

 

 

Last modified: Thursday, 3 January 2019, 11:27 PM