Beverage can is thrown upward and then falls back down to the floor. as usual, a y axis extends upward (positive direction). which of the following best describes the acceleration of the can during its free flight? a) -9.8 m/s^2, then momentarily zero, then +9.8 m/s^2b) +9.8 m/s^2 throughoutc) -9.8 m/s^2 throughoutd) zero throughoute) +9.8 m/s^2, then momentarily zero, then -9.8 m/s^2

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

Emmy kicks a soccer ball up at an angle of 45° over a level field. she watches the ball's trajectory and notices that it lands, two seconds after being kicked, about 20 m away to the north. assume that air resistance is negligible, and plot the horizontal and vertical components of the ball's velocity as a function of time. consider only the time that the ball is in the air, after being kicked but before landing. take "north" and "up" as the positive ‑ and ‑directions, respectively, and use ≈10 m/s2 for the downward acceleration due to gravity.

An astronaut on the moon throws a baseball upward. the astronaut is 6 ft, 6 in. tall, and the initial velocity of the ball is 3030 ft per sec. the height s of the ball in feet is given by the equation s equals negative 2.7 t squared plus 30 t plus 6.5s=−2.7t2+30t+6.5, where t is the number of seconds after the ball was thrown. complete parts a and b.