Achild throws a ball up in the air to a height of 3.5 m and catches it at the same point from which he threw it. the ball is in the air for a total of 1.7 s. what is the average velocity of the ball? explain your answer.

Modify the equation fδt=δ (mv) to find the force of friction.

What is the acceleration of a spaceship that is initially at rest and then speeds up to 220 m/s in 20 seconds

Part 1: a magnetic levitation or maglev train rides rails without touching them. explain how this works using your data. include the appropriate magnet drawing in your answer. part 2: two objects are near a bar magnet. one is about 1 cm away, while the other is 6 cm away. compare and contrast the magnetic force that affects each object. use your data to answer the question