Ck-12 Refraction
2/10
SKILL LEVEL
To be de
Light coming straight from a laser pointer passes from air into a
tub of liquid. It hits the surface of the liquid at an angle of 28°
from vertical, and continues into the liquid at an angle of 22°.
What is the index of refraction of the substance in the tub? n =

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.