Two blocks, joined by a string, have masses of 6.0 and 9.0 kg. They rest on a frictionless horizontal surface. A 2nd string, attached only to the 9-kg block, has horizontal force = 30 N applied to it. Both blocks accelerate. Find the tension in the string between the blocks. (12 N) A 10-kg mass and a 2.0-kg mass are connected by a light string over a massless, frictionless pulley. If g = 9.8 m/s, what is the acceleration of the system when released? (6.5 m/s) A 15-kg block rests on a level frictionless surface and is attached by a light string to a 5.0-kg hanging mass where the string passes over a massless frictionless pulley. If g = 9.8 m/s, what is the tension in the connecting string? (37 N) A boxcar of mass 200 tons at rest becomes uncoupled on a 2.5 grade. If the track is considered to be frictionless, what speed does the boxcar have after 10 seconds? (4.3 m/s) . An elevator weighing 20 000 N is supported by a steel cable. What is the tension in the cable when the elevator is being accelerated upward at a rate of 3.00 m/s? (26 100 N)