Which of the following means an object is speeding up? a. it's velocity is decreasing b. it's velocity is increasing c. it's acceleration is increasing d. it's acceleration is decreasing

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve

Why is the energy that results from a roller coaster's position at the top of a hill referred to as potential energy?

Select all the correct answers. which changes will increase the rate of reaction during combustion? decreasing the area of contact between the reactants adding more oxygen to the reaction removing heat from the reaction changing the reactants from solid form to powdered form lowering the exposure of the reactants to air