An attacker at the base of a castle wall 3.95 m high throws a rock straight up with speed 8.20 m/s from a height of 1.50 m above the ground. (a) Will the rock reach the top of the wall? O Yes O No (b) If so, what is its speed at the top? If not, what initial speed must it have to reach the top? m/s (c) Find the change in speed of a rock thrown straight down from the top of the wall at an initial speed of 8.20 m/s and moving between the same two points. m/s

An attacker at the base of a castle wall 3.80 m high throws a rock straight up with speed 8.40 m/s from a height of 1.40 m above the ground. (a) Will the rock reach the top of the wall? Yes, No     (b) If so, what is its speed at the top? If not, what initial speed must it have to reach the top? m/s(c) Find the change in speed of a rock thrown straight down from the top of the wall at an initial speed of 8.40 m/s and moving between the same two points. m/s(d) Does the change in speed of the downward-moving rock agree with the magnitude of the speed change of the rock moving upward between the same elevations? Yes, No     (e) Explain physically why it does or does not agree.

A roller-coaster goes over a 12 m tall hill then approaches a 30 m hill. What is the minimum velocity the roller-coaster would need when going over the 12 m hill to make it to the top of the 30 m hill?   Question 4 options:   254.8 m/s   Not enough information to answer   18.78 m/s   15.96 m/s

A small block slides down a frictionless track whose shape is described by y = (x^2) /d for x<0 and by y = -(x^2)/d for x>0.  Here we go again this time, d = 4.13 m. Suppose the block starts on the track at x = 0. What minimum initial velocity (moving to the right) must the block have such that it will leave the track at x = 0 and go into freefall?      9.00 m/s      6.36 m/s      12.29 m/s      9.33 m/s