Heat Transfer in Nature Class 7 Questions and Answers Science Chapter 7
Heat Transfer in Nature Class 7 Questions and Answers Science Chapter 7 1. Choose the correct option in each case. (i) Your father bought a saucepan made of two diff erent materials, A and B, as shown in Fig. 7.14. The materials A and B have the following properties — (a) Both A and B are good conductors of heat (b) Both A and B are poor conductors of heat (c) A is a good conductor and B is a poor conductor of heat (d) A is a poor conductor and B is a good conductor of heat Answer: (c) A is a good conductor and B is a poor conductor of heat. (ii) Pins are stuck to a metal strip with wax and a burning candle is kept below the rod, as shown in Fig. 7.15. Which of the following will happen? (a) All the pins will fall almost at the same time (b) Pins I and II will fall earlier than pins III and IV (c) Pins I and II will fall later than pins III and IV (d) Pins II and III will fall almost at the same time Answer: (d) Pins II and III will fall almost at the same time. (iii) A smoke detecto...