On a sunny day, a distracted driver on his cellphone noticed a tree way too late. He screeches as he slowed down but still hit the tree at 20 km/h. Afterwards, it was measured that he left a tire mark of 6.0 m in length (tire marks for only front tires drawn above). a) Calculate the car’s speed, in km/h, before the driver started slowing down. Define a system, draw energy state diagrams, and include a FBD for any forces. b) If this happened on an uphill slope of 6°, what would have been the car’s initial speed in km/h?

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.)