What is the first velocity of the car with four washers at
the 0.25 meter mark?
m/s
Calculate the first and second velocities of the car with
four washers attached to the pulley, using the formulas
V1 = 0.25 m/ty, and v2 = 0.25 m/(t2-t1)
where to and ty are the average times the car took to
reach the 0.25 and the 0.50 meter marks. Record these
velocities, to two decimal places, in Table E
What is the second velocity of the car with four
washers at the 0.50 meter mark?
m/s

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?

Aspring has a natural length of 8 m. if a 12-n force is required to keep it stretched to a length of 10 m, how much work w is required to stretch it from 8 m to 16 m? (round your answer to two decimal places.)

Arunner is jogging at a steady 3.6 km/hr. when the runner is 2.9 km from the finish line, a bird begins flying from the runner to the finish line at 14.4 km/hr (4 times as fast as the runner). when the bird reaches the finish line, it turns around and flies back to the runner. even though the bird is a dodo, we will assume that it occupies only one point in space, i.e., a zero-length bird. how far does the bird travel? (b) after this first encounter, the bird then turns around and flies from the runner back to the finish line, turns around again and flies back to the runner. the bird repeats the back and forth trips until the runner reaches the finish line. how far does the bird travel from the beginning? (i.e. include the distance traveled to the first encounter)