11. An explosion breaks a 27.0-kg object initially at rest into three parts. Part (1) has a mass m₁ 5.20-kg and a velocity of 59.0 m/s due east. Part (2) has a mass m2 5.20-kg and a velocity of 78.0 m/s due south. What is the magnitude of the velocity of part (3)? m/s = =

A 0.14 kg bead slides on a straight frictionless wire and moves with a velocity of 9.5 m/s to the right. The bead collides with a larger 0.12 kg bead that is initially at rest. After the collision, the smaller bead moves with a velocity of 0.73076923076923 m/s. (use many decimal points in your answer in order to make sure you get it exact) a.What is the large bead's velocity after the collision? b.What is the total kinetic energy of the system of beads after the collision? c.What was the total kinetic energy of the system of beads before the collision?

2. A 62 kg student stands on a 36 kg cart that is free to move in any direction. The cart and student are moving together with a velocity of 2.7 m/s [S]. The student then starts to walk so that her velocity is 3.1m/s [ E25oN] relative to the floor. Calculate the new velocity of the cart.

During a car collision, the knee, thighbone, and hip can sustain a force no greater than 4000 NN. Forces that exceed this amount could cause dislocations or fractures. Assume that in a collision a knee stops when it hits the car's dashboard. Also assume that the mass of the body parts stopped by the knee is about 20% of the total body mass. The person with a mass of 90 kgkg is initially traveling at 18 m/sm/s (40 mi/hmi/h).  What minimum stopping time interval in needed to avoid injury to the knee?  What is the minimum stopping distance?