A runner is dragging in a straight line at a steady we are equals 7.4 km/hour. When the runner is L equals 6.3 from the finish line, a bird begins flying straight from the runner to the finish line VV equals 22.2 km/hour parentheses three times as fast as the runner). When the bird reaches the finish line, it turns around and flies directly back to the runner. What cumulative distance does a bird travel? Even though the bird is another assume that it occupies only one point space, travels in a straight line, and I can turn with a loss of speed. Answer in units of kilometers

Aspring has a relaxed length of 33 cm (0.33 m) and its spring stiffness is 6 n/m. you glue a 76 gram block (0.076 kg) to the top of the spring, and push the block down, compressing the spring so its total length is 15 cm. you make sure the block is at rest, then at time t=0 you quickly move your hand away. the block begins to move upward, because the upward force on the block by the spring is greater than the downward force on the block by the earth. calculate y vs. time for the block during a 0.09-second interval after you release the block, by applying the momentum principle in three steps each of 0.03-second duration.