Q 16a) Both of them are used to measure human body temperature
b) Thermometer A is a liquid- in-glass clinical thermometer, while Thermometer B is an ear thermoscan.
17 a) She had placed her eye at the wrong position.
b) She should place her eye at the same level as the liquid level
c) 47 degrees celcius
18) Tick: Geyser, Sun
18b) Natural- Geyser, sun Man-made- Oven Clothes dryer
19a) Heat gain b) Heat loss c) Heat loss
20a) The metal tracks expand on hot days, so the gaps become narrower
b) the sun
c) If there were no gaps, the track will buckle on hot days, causing trains to derail.
21) the wire will contract and break. This is because the cold teperature will cause the thin wire to lose heat and contract.
22 (a) True (b) True (c) True (d) False
23 (a) Material C is most suitable
(b) IT is the poorest ocnductor of heat among the four as it took the longest time for the wax to melt.
