4 Question ' A car travels 10 km east from the origin with an average velocity of 20 km h". Then make a sharp left turn and travel for another 45 minutes with an average velocity of 12 m/s. An eagle was also released from the origin and follows the shortest path possible. Suppose the two leave the origin at t = 05, find the constant acceleration (magnitude and direction) of the eagle so they arrive at the nal position simultaneously. The mass of copper atom is 1.06)(10'25 kg, while the density of copper is 8920 kg m'3. Find: (a) The number of copper atoms per 2 cm3 of copper (b) How many copper atoms can t in a copper wire of radius 1mm with length 0.5m? 3 1D Use a = -g Pepito and Tommy went to a building to investigate free-fall. Pepito sits on the top of the 100m building, while Tommy is at the 50m. If they have an identical pebble and the air resistance can be ignored. Find: (a) Distance before tommy let go his pebble so both pebbles will simultaneously hit the ground (b) The initial velocity Pepito must input so both pebbles will simultaneously hit the ground2 Vectors Note: The sign convention for angle may not apply The concurrent vectors A and B were combined to yield a resultant vector C, as shown in the figure below. Find the angles a, B, and Y. = 4m B C = 1 . 8 0 3 m A : 3m