Homework Notes

HW 9

* For each part of these problems, be very careful about what you choose as the system and what you are using as initial and final states.

** Just find equations that could be solved for the mass of the X+ particle. Be sure that you have as many equations as unknowns. Use θ for the angle that the pion is deflected and f for angle between the direction that the X+ particle goes and the initial direction of the pion. When relating the energy of the particles to their momentum, don’t assume that they are traveling slowly.

“39”       A 1-kg puck is sliding at 3 m/s and collides with a 2-kg puck which was initially at rest. After the collision, the 1-kg puck is traveling at 2.24 m/s at an angle of 63.4° from the direction it was originally going.

(a)     What is the velocity (magnitude and direction) of the larger puck after the collision? (You may not assume that collision is elastic!)

(b)     Was the collision elastic?

Extra Credit: For two extra points each, find numerical answers to part (c) of 9.P.21 (the height h of the block) and to 9.P.26 (the mass of the X+ particle).