Russ makes the diagram below to organize his notes about how Newton's first law describes objects at equilibrium.

On a mild saturday morning while people are working inside, the furnace keeps the temperature inside the building at 23degreesc. at noon the furnace is turned off, and the people go home. the temperature outside is a constant 16degreesc for the rest of the afternoon. if the time constant for the building is 3 hr, when will the temperature inside the building reach 18degreesc? if some windows are left open and the time constant drops to 2 hr, when will the temperature inside reach 18degreesc?

When you notice something that is happening, what are you making? a. an observation b. a law c. a theory d. an experiment

Abook is sitting on a table, completely still. what would happen if gravity suddenly stopped affecting the book? a. the book would move upward. b. the book would stay where it is. c. the book would fall. d. the book would move sideways.