# AP Physics C Free response Questions: Kinematics and Statics

### Motion in one and two Dimensions

A projectile is launched from the top of a cliff above level ground. At launch the projectile is 35 meters above the base of the cliff and has a velocity of 50 meters per second at an angle 37° with the horizontal. Air resistance is negligible.  Consider the following two cases and use g = 10 m/s2, sin 37° = 0.60, and cos 37° = 0.80.

Case I: The projectile follows the path shown by the curved line in the following diagram. Calculate the total time from launch until the projectile hits the ground at point C.

Calculate the horizontal distance R that the projectile travels before it hits the ground.

Calculate the speed of the projectile at points A, B and C.

Case II: A small internal charge explodes at point B in the above diagram, causing the projectile to separate into two parts of masses 6 kilograms and 10 kilograms.  The explosive force on each part is horizontal and in the plane of the trajectory.  The 6‑kilogram mass strikes the ground at point D, located 30 meters beyond point C, where the projectile would have landed had it not exploded  The 10‑kilogram mass strikes the ground at point E. Calculate the distance x from C to E.