"At the end of the lab all of the matter (such as the string, the ball and the books) stayed in the area. The potential energy, that was stored in the ball on the high shelf and suspended weightsas well as the stored mechanical energy of the sling shot, had left the system in the form of sound, motion and heat.
What type of energy system (open, closed or isolated) is represented by the lab device and why? "

On a horizontal frictionless surface, a small block with mass 0.200 kg has a collision with a block of mass 0.400 kg. immediately after the collision, the 0.200 kg block is moving at 12.0 m/s in the direction 30° north of east and the 0.400 kg block is moving at 11.2 m/s in the direction 53.1° south of east. use coordinates where the +x-axis is east and the +y-axis is north.(a) what is the total kinetic energy of the two blocks after the collision (in ) what is the x-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your ) what is the y-component of the total momentum of the two blocks after the collision? (indicate the direction with the sign of your answer.)