Atrain car with mass m1 = 663 kg is moving to the right with a speed of v1 = 8.8 m/s and collides with a second train car. the two cars latch together during the collision and then move off to the right at vf = 5.3 m/s. 1)what is the initial momentum of the first train car?

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .