Ablock of mass m=5.20\; \mathrm{kg}m=5.20kg is being suspended at rest by an extended spring of spring constant k=36.0\; \mathrm{n/m}k=36.0n/m and an external force f=20.0\; \mathrm{n}f=20.0n downward. the spring is attached to the ceiling and has an extended length of s=2.45\; \mathrm{m}s=2.45m. what is the relaxed length s_0s 0 of the spring?

The heater element of a 120 v toaster is a 5.4 m length of nichrome wire, whose diameter is 0.48 mm. the resistivity of nichrome at the operating temperature of the toaster is 1.3 × 10-6 ω·m. the toaster is operated at a voltage of 120 v. (a) what is the power drawn by the toaster? (b) if the cost of electricity is 12 ¢ per kilowatt-hour, and it takes 2 minutes to toast bread, how much does it cost for toasted bread? (c) when the heater element is at room temperature, is the resistivity in the nichrome wire greater than, less than, or equal to it’s resistivity when at operating temperature? explain.