A person carries a plank of wood 1.8 m long with one hand pushing down on it at one end with a force F1 and the other hand holding it up at 55 cm from the end of the plank with force F2. If the plank has a mass of 18 kg and its center of gravity is at the middle of the plank, what are the magnitudes of the forces F1 and F2?

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.)