A 20 kg dog runs at + 2.5 m/s and collides with a 10 kg piece of on a frozen lake. After the collision we know that the 20 kg dog was moving - 2 m/s BACKWARDS, and the ice was moving the same way as the dog at - 5.0 m/s How fast AND in which direction was the piece of ice moving BEFORE the collision?

the independent variable, the one that is intentionally manipulated, is whether or not the car hits the barrier.

the dependent variable, the one that you measure the response in, is the distance that the washers travel.

heat the gas and measure the pressure

what is the speed of a softball that travels 20m in 2secs

speed = 20/2 = 10 m/s