Copper wires used to transport electrical current heat up because of the resistance of the wire. If a 140-g wire at 55°C gains 1280 J of heat, what is its final temperature? 

11. The initial temperature of a 344 g sample of iron is 18.2 deg C. If the sample absorbs 2.25 kJof energy as heat, what is its final temperature?

An aluminum interconnect within a silicon microelectronic device has a hemispherical cross section with a radius of 0.5 µm and a length of 100 µm. What is its resistance at room temperature? The operating temperature of the device is 60 degrees C. Would the resistance of the interconnect increase, decrease, or stay the same? Briefly explain.

A student designs an ammeter (a device that measures electrical current) that is based on the electrolysis of water into hydrogen and oxygen gases. When electrical current of unknown magnitude is run through the device for 3.50 min , 13.5 mL of water-saturated H2(g) is collected. The temperature and pressure of the system are 25 ∘C and 715 torr.

The vapor pressure of water changes with temperature, as shown here.
T (∘C) P (torr)
21 18.7
22 19.8
23 21.1
24 22.4
25 23.8
26 25.2
27 26.7
28 28.4
29 30.0
30 31.8