Superman throws a boulder of weight 3800 n at an adversary on the surface of the earth, where the magnitude of the acceleration due to gravity, g = 9.80 m/s2 . what horizontal force must superman apply to the boulder to give it a horizontal acceleration of 12.8 m/s2 ?

The roller coaster from problem #1 then tops a second hill at 15.0 m/s, how high is the second hill? 91.5 m 79.2 m 80.0 m 68.5 m

If a rock is thrown upward on the planet mars with a velocity of 12 m/s, its height (in meters) after t seconds is given by h = 12t − 1.86t2. (a) find the velocity of the rock after two seconds. m/s (b) find the velocity of the rock when t = a. 12−3.72a m/s (c) when will the rock hit the surface? (round your answer to one decimal place.) t = s (d) with what velocity will the rock hit the surface? m/s

The ph is the a.independent variable b.the dependent variable c.control group