A52.0-kilogram skateboarder does a trick on a half-pipe. during the trick, he reaches a speed of 8.90 m/s. the radius of the half-pipe ramp is 3.00 meters. what is the minimum centripetal force necessary to keep the skater on the ramp? explain your answer

Air pressure is measured in pascals. for a professional american football game, the ball should be inflated to about 90,000 pascals. scientists studied the effects of air temperature on the pressure inside american footballs by taking these steps: 1. prepare 100 footballs. 2. measure each football's air pressure. 3. divide footballs into 10 groups. 4. place the groups in different lockers cooled to different air temperatures. 5. after 12 hours, remove the footballs from lockers. 6. measure each football's pressure again. 7. compare the new pressures to the starting pressures. what two terms best describe the variable "air pressure inside the football" in this experiment? independent, qualitative independent, quantitative dependent, qualitative dependent, quantitative

The equation below shows a chemical reaction. a + b + heat —> c + d according to the law of conservation of energy, which statement is true? a. the reactants absorb heat because they have less energy than the products. b. the products release heat because they have more energy than the reactants. c. the reactants generate heat because they have more energy than the products. d. the products require heat to form because they have less energy than the reactants.

1. what is boyle’s law? • state the definition of the law in words. • what are the assumptions of boyle’s law? • write at least one mathematical equation that represents the law. • what can be calculated with boyle’s law? • using a gas-filled balloon as an example, describe what is happening to the gas molecules inside the balloon before and after you squeeze it.