11. Momentum & Impulse
Adding Mass to a Moving System
05:21
Learn with other creators
Practice this topic
- Multiple Choice
A 40-kg skater runs parallel to a 3-kg skateboard. Both are moving to the right at 10m/s. The skater jumps on the board, and they move continue moving right (i.e. no change in direction). Calculate the final speed of the system.
1215views33rank - Multiple ChoiceA 2.4 kg metal disk is horizontal and is spinning at 30 rpm. A second disk with the same radius, but with a mass of 5.2 kg is initially not spinning and is lowered gently onto the spinning disk. The system of the two disks is then isolated, such that there is no external torque on it. The disks scrape against each other until they are moving with the same speed. What is the final rotational speed of the disks, in rpm?912views
- Textbook Question
Three identical train cars, coupled together, are rolling east at speed v0. A fourth car traveling east at 2v0 catches up with the three and couples to make a four-car train. A moment later, the train cars hit a fifth car that was at rest on the tracks, and it couples to make a five-car train. What is the speed of the five-car train?
1020views - Textbook Question
A 10-m-long glider with a mass of 680 kg (including the passengers) is gliding horizontally through the air at 30 m/s when a 60 kg skydiver drops out by releasing his grip on the glider. What is the glider's velocity just after the skydiver lets go?
1025views - Textbook Question
A 10,000 kg railroad car is rolling at 2.0 m/s when a 4000 kg load of gravel is suddenly dropped in. What is the car’s speed just after the gravel is loaded?
542views - Textbook Question
A 7150-kg railroad car travels alone on a level frictionless track with a constant speed of 15.0 m/s. A 3650-kg load, initially at rest, is dropped onto the car. What will be the car’s new speed?
740views