Block 1, of mass m1 = 2.70 kg , moves along a frictionless air track with speed v1 = 23.0 m/s . it collides with block 2, of mass m2 = 33.0 kg , which was initially at rest. the blocks stick together after the collision. (a) find the magnitude pi of the total initial momentum of the two-block system.
(b) find vf, the magnitude of the final velocity of the two-block system.
(c) what is the change? k=kfinal? kinitial in the two-block system's kinetic energy due to the collision?

You have two photos of a person walking. one shows the person at the corner of third and main streets, the other shows the person at the corner of tenth and main streets. there are lampposts at every corner in this town, and the first picture shows it to be 10: 32: 00 exactly. the second picture shows it to be 10: 49: 30. you know three facts: (1) all of the clocks are synchronized; (2) there are exactly 12 equal-sized blocks per kilometer in this town; and (3) the streets that cross main in this area are numbered consecutively, with no interruptions. what is the person’s average speed in kilometers per hour?