As the roller coaster cars go down the first hill, they go (1.) (faster and faster/slower and slower). This change in speed means their (2.) (velocity/reference point) also changes. When the cars climb the next hill, they (3.) (speed up/slow down). This causes their (4.) (velocity/reference point) to change again. When the cars hit a curve, their (5.) (velocity/reference point) changes again! (6.) (Acceleration/Speed) is a measure of the change in (7.) (velocity/motion) during a period of time.

Amachine, modeled as a simple spring-mass system, oscillates in simple harmonic motion. its acceleration is measured to have an amplitude of 5,000 mm/s with a fre- quency of 10 hz. compute the maximum displacement the machine undergoes during this oscillation.

While studying chemical reactions and conservation of matter, sarah's class conducted a variety of experiments. sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. the students lit the candle and let it burn to completion. all that was left was wax and charred candle wick. per their teacher's instructions, the students found the mass of the products. their data can be seen in the data table. formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter. a) the students could repeat the experiment using different candles; there might have been a flaw in the candle. b) the experiment should be repeatable. the students should run several trials and then take an average of the after mass in each trial. c) the students should have someone in the class check their measurement skills as they repeat the experiment. they may have made an error using the balance. d) the students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed. submit

Which levels of government establish and implement educational requirements for minors