Is the specified change in the following objects’ thermal energies due to a flow of heat (A), work (B), or some other flow of energy (E)?
(a) A hot cup of tea on a table becomes cooler with time.
(b) A meteorite entering the atmosphere becomes hot.
(c) Liquid nitrogen poured on a slab of ice boils furiously. (Liquid nitrogen’s boiling point is 77 K.)
(d) Infrared laser light falling on a metal slab makes it hot.
(e) A drill bit gets hot as it drills a hole in a metal slab.
(a) A hot cup of tea on a table becomes cooler with time. - A
(b) A meteorite entering the atmosphere becomes hot. - B
(c) Liquid nitrogen poured on a slab of ice boils furiously. (Liquid nitrogen’s boiling point is 77 K.) - A
(d) Infrared laser light falling on a metal slab makes it hot. - E
(e) A drill bit gets hot as it drills a hole in a metal slab. - B
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