A ball of mass 0.193 kg has a velocity of 1.45 i m/s; a ball of mass 0.290 kg has a velocity of -0.407 i m/s. They meet in a head-on elastic collision. Find the speed of their center of mass after the collision.

An astronaut on the moon throws a baseball upward. the astronaut is 6 ft, 6 in. tall, and the initial velocity of the ball is 3030 ft per sec. the height s of the ball in feet is given by the equation s equals negative 2.7 t squared plus 30 t plus 6.5s=−2.7t2+30t+6.5, where t is the number of seconds after the ball was thrown. complete parts a and b.

An alpha particle with kinetic energy 12.5 mev makes a collision with lead nucleus, but it is not "aimed" at the center of the lead nucleus, and has an initial nonzero angular momentum (with respect to the stationary lead nucleus) of magnitude l = p0 b, where p0 is the magnitude of the initial momentum of the alpha particle and b=1.40×10−12 m. (assume that the lead nucleus remains stationary and that it may be treated as a point charge. the atomic number of lead is 82. the alpha particle is a helium nucleus, with atomic number 2.) what is the distance of closest approach?

Mackinzie walks 4 blocks west, then 2 blocks south, then 4 blocks east, and,finally, 1 block south. what is the magnitude of her total displacement duringthis walk (in blocks)?