Two astronauts X and Y of identical mass are connected by a taut cable of negligible mass and are initially at rest with respect to a nearby space station. Astronaut X pulls with considerable force towards herself. Which of the following describes the direction of the velocity of the center of mass of the astronauts after pulls on the cable? a) the center of mass moves towards X b) the center of mass moves towards Y c) the center of mass does not move

Highway safety engineers want to design roadside barriers that will crumple in the event that a car drives off the road and collides with them, slowing down the car more gradually. The average person has a mass of 68 kg and travels on a highway at a velocity of 27 m/s. If the engineers know that the maximum force that a person can safely withstand is 1180 N, approximately how much time is required to crumple the barrier to safely slow the person with this force?

A man with mass m1 = 51 kg stands at the left end of a uniform boat with mass m2 = 168 kg and a length L = 3.3 m. Let the origin of our coordinate system be the man’s original location as shown in the drawing. Assume there is no friction or drag between the boat and water. 1) If the man now walks to the right edge of the boat, what is the location of the center of mass of the system?     2) After walking to the right edge of the boat, how far has the man moved from his original location? (What is his new location?)   3) After the man walks to the right edge of the boat, what is the new location the center of the boat?   4) Now the man walks to the very center of the boat. At what location does the man end up?

Two persons A and B who are at rest on an ice skating rink, push each other so that A acquires a velocity of 11.5 m/s towards North. If the mass of person A is 55 kg and that of B is 43 kg. What is the velocity acquired by B and in which direction?Your answer must be in the order Velocity / Direction.