A Projectile of mass 0.277 kf is shot from a cannon. The end of the cannon's barrel is at heiht 6.8 m. The initial velocity of the projectile has a horizontal component of 6.1 m/s. The projectile rises to a maximum height above the end of the cannon's barrel and strikes th ground a horizontal distance past the end of the cannon;s barrel. What is the time it takes for the projectile to reach its maximm height? The acceleration of gravity is 9.8 m/s^2.

The solar panels used by mark function because of the photoelectric effect. light shines on the cells causing electrons to be ejected from the metal, which produces an electric current. at night on mars, no light will fall on the solar cells and no electric current will be generated. according to your notes, what type of light is typically needed to cause the photoelectric effect? a)visible b)ultraviolet c)infrared

If two parallel light rays hit a mirror, they will not be parallel to each other after they reflect.

In an old-fashioned amusement park ride, passengers stand inside a 3.0-m-tall, 5.0-m-diameter hollow steel cylinder with their backs against the wall. the cylinder begins to rotate about a vertical axis. then the floor on which the passengers are standing suddenly drops away! if all goes well, the passengers will “stick” to the wall and not slide. clothing has a static coefficient of friction against steel in the range 0.60 to 1.0 and a kinetic coefficient in the range 0.40 to 0.70. part a what is the minimum rotational frequency, in rpm, for which the ride is safe? express your answer using two significant figures. f f = rpm