out convection of water is correct? * Hot water sinks and cold water rises because hot water has higher density than cold water. Hot water rises and cold water sinks because hot water has higher density than cold water. Hot water rises and

Which of the following statement correctly describes heat? * Heat is the energy stored in a body at a certain temperature. Heat is the degree of hotness of a body. Heat is the energy transferred from high temperature to low temperature. Q2. In solids, heat is mainly transferred through molecules' vibrations. This process is called __________. * radiation convection conduction Q3. Which of the following materials is a good conductor of heat? * glass plastic aluminium Q4. Metals are always better conductors of heat than most non-metals because they have __________ to transfer heat other than molecules' vibrations. * free electrons free atoms free protons Q5. Which of the following statements about air and water is correct? * Both air and water are poor conductors of heat. Both air and water are good conductors of heat. Air is a poor conductor of heat, but water is a good conductor of heat. Air is a good conductor of heat, but water is a poor conductor of heat. Q6. Heat is transferred effectively by __________ in liquids and gases. * radiation conduction convection Q7. Which of the following statements about convection of water is correct? * Hot water sinks and cold water rises because hot water has higher density than cold water. Hot water rises and cold water sinks because hot water has higher density than cold water. Hot water rises and cold water sinks because hot water has lower density than cold water. Hot water sinks and cold water rises because hot water has lower density than cold water. Q8. Which of the following processes does NOT require a medium to transfer heat? * conduction radiation convection Q9. According to the video, we feel the heat from the radiator mainly by __________. * conduction radiation convection Q10. Comparing with the same object painted in silvery, object painted in BLACK absorbs heat _____(a)_____ and emits heat _____(b)_____. * (a): slower ; (b): slower (a): faster ; (b): slower (a): faster ; (b): faster (a): slower ; (b): faster Q11. The temperature of air in a greenhouse is usually much higher than outdoor. Which of the following is the main reason? * The glass top of greenhouse does not allow hot air to lose heat by convection. The glass walls of greenhouse absorbs large amount of heat from the Sun. The glass walls of greenhouse conducts heat quickly from outdoor to indoor. Q12. Near the end of the video, which sports is used to act as an analogy to the three heat transfer processes: conduction, convection and radiation? * Table tennis Football Basketball Volleyball Q13. What is installed between the inner wall and the outer wall of a portable cooler in order to keep the drinks in the cooler cool? * good conductor of heat poor conductor of heat good absorber of heat poor absorber of heat ice Q14. Which of the following is NOT a special design of a vacuum flask to keep water warm for long time? * The outer glass wall is painted in silvery. The layer between the double-glass wall is a vacuum. The stopper is made of plastic. The inner glass wall is painted in black. Q15. Feathers on birds' bodies can keep birds warm. Which of the following statements describes the main reason? * Feathers are poor conductor of heat so that the rate of heat lost by conduction is reduced. Feathers are always white in color so that the rate of heat lost by radiation is reduced. Feathers trap air so that the rate of heat lost by convection is reduced.