A rolling freight car collides with an identical freight car at rest. After coupling they roll with a speed of 2 m/s. From this information the initial speed of the rolling freight car was 5 m/s 6 m/s ● 4 m/s 8 m/s When two objects collide in a closed system and there are no external forces acting on them, what happens to the total momentum of the system? no change it decreases it fluctuates It increases

From what might be a possible scene in the comic book The X-Men, the Juggernaut (mJ) is charging into Colossus (mC) and the two collide. The initial speed of the Juggernaut is vJi and the initial speed of Colossus is vCi. After the collision, the final speed of the Juggernaut is vJf and the final speed of Colossus is vCf as they each bounce off of the other, heading in opposite directions. a. What is the impulse experienced by the Juggernaut? b. What is the impulse experienced by Colossus? c. In your own words, explain how these impulses must compare with each other and how they are related to the average force each superhero experiences during the collision.

An astronaut out on a spacewalk to construct a new section of the International Space Station walks with a constant velocity of 2.00 m/s on a flat sheet of metal placed on a flat, frictionless, horizontal honeycomb surface linking the two parts of the station. The mass of the astronaut is 75.0 kg, and the mass of the sheet of metal is 245 kg. a. What is the velocity of the metal sheet relative to the honeycomb surface? b. What is the speed of the astronaut relative to the honeycomb surface?

A 2.00 1O3-kg car moving cast at 10.0 m/s collides with a 3.00 103-kg car moving north. The cars stick together and move as a unit after the collision, at an angle of 40.0 north of east and a speed of 5.22 m/s. Find the speed and direction of the 3.00 103-kg car before the collision.

A ballistic pendulum is used to measure the speed of bullets. It comprises a heavy block of wood of mass M suspended by two long cords. A bullet of mass m is fired into the block horizontally. The block, with the bullet embedded in it, swings upward (Fig. P10.70). The center of mass of the combination rises through a vertical distance h before coming to rest momentarily. In a particular experiment, a bullet of mass 40.0 g is fired into a wooden block of mass 10.0 kg. The blockbullet combination is observed to rise to a maximum height of 20.0 cm above the blocks initial height. a. What is the initial speed of the bullet? b. What is the fraction of initial kinetic energy lost after the bullet is embedded in the block? FIGURE P10.70

If the resultant of all the external forces acting on a system of particles is zero, then from an inertial frame,one can surely say that : A linear momentum of the system does not change in time kinetic energy of the system does not change in time C angular momentum of the system does not change in time potential energy of the system does not change in time

A ball moving with a speed of 9m/s strikes an identical stationary ball such that after collision, the direction of each ball makes an angle 30° with the original line of motion (see Fig.). Find the speed of the stationary ball after the collision. 30° 30° A) 10.23 m/s B) 7.16 m/s C) 6.38 m/s D) 5.19 m/s E) 4.86 m/s

The velocity of a ball changes from < 6, -6, 0 m/s to 5.92, -6.32, 0 m/s in 0.04 s, due to the gravitational attraction of the Earth and to air resistance. The mass of the ball is 140 grams. (a) What is the acceleration of the ball? (m/s)/s = X (b) What is the rate of change of momentum of the ball? dp/dt= (kg. m/s)/s (c) What is the net force acting on the ball? N net =

A raccoon is sitting on one end of the log and notice that there is an delicious apple just above the other end of the log on the still water as shown on figure. The raccoon starts to walk along the log of 10 meters length at a constant velocity of 0.1 m/s with respect to the log. Neglect its size. The mass of the raccoon is m = 20 kg and the mass of the log is M = 90 kg. Depending on your choice of method, you may answer (b) before (a). You should solve both methods (Center of Mass and Conservation of Momentum). a) As the raccoon is walking, what is the velocity of the log with respect to the shore? b) When the raccoon reaches the opposite end of the log, how far is he horizontally from the apple he desires?

A 86-kg astronaut and a 1200-kg satellite are at rest relative to the space shuttle. The astronaut pushes on the satellite, giving it a speed of 0.18 m/s directly away from the shuttle. Seven-and-a-half seconds later the astronaut comes into contact with the shuttle What was the initial distance from the shuttle to the astronaut?Express your answer using two significant figures.