A railroad flatcar of mass 3,000 kilograms rolls to the right at 10 meters per second and collides with a flatcar of mass 2,000 kilograms that is rolling to the left at 5 meters per
second. The flatcars couple together. Their speed after the collision is

What are igneous intrusions and extrusions

Students design a model roller-coaster track. they place a rubber ball at the highest point on the track and let it go. the ball rolls along the track pulled only by the force of gravity. eventually, it comes to a stop. which change to the design will result in the ball moving the greatest distance?

If the work required to stretch a spring 3 ft beyond its natural length is 15 ft-lb, how much work is needed to stretch it 27 in. beyond its natural length?