Equal-mass samples of three different solids are placed on identical electrical…
PHYSICS · Multi-part · A Level · Physics · Further mechanics and thermal physics · Further mechanics and thermal physics
Problem
Equal-mass samples of three different solids are placed on identical electrical heaters that each deliver the same constant amount of thermal energy for 120 s. Relevant properties of the materials are shown below.
Material Specific heat (J kg⁻¹ °C⁻¹)
Aluminum 900
Brass 380
Quartz glass 840
The heaters are turned off after 120 s, and no energy is lost to the surroundings during the heating period.
(a) Rank the three samples from highest to lowest final temperature after the 120 s heating interval. Explain your reasoning qualitatively without performing detailed numerical calculations.
(b) In a second trial, the brass sample alone is heated for twice as long (240 s) with the same heater while the aluminum and quartz glass samples are again heated for 120 s. Compare the final temperature of the brass sample in the second trial to the final temperature of the quartz glass sample in the first trial. Support your comparison with proportional reasoning or an order-of-magnitude estimate.
(c) Describe how differences in atomic arrangement and bonding lead to the differences in specific heat listed in the table. Your explanation should connect microscopic structure to the macroscopic thermal behavior observed in parts (a) and (b).