Two blocks are at rest on a horizontal frictionless surface with ...

[eruditmonkey@yahoo.com]

Two blocks are at rest on a horizontal frictionless surface with a compressed spring between them. The 15.0-kg block accelerates when the string holding the system in compression is cut and the 30.0-kg box accelerates in the opposite direction. What is the magnitude of the force from the expanding spring on the 30.0-kg box when the 15.0-kg box is undergoing an acceleration of 5.00 m/s2?
 a. 37.5 N
  b. 150 N
  c. 225 N
  d. 75.0 N
  e. 0 N

Question 2

A 16.0-kg mass and a 2.25-kg mass are connected by a light string over a massless, frictionless pulley. If g = 9.8 m/s2, what is the acceleration of the system when released?
 a. 13.0 m/s2
  b. 7.38 m/s2
  c. 179 m/s2
  d. 9.80 m/s2
  e. 1.86 m/s2

[livaneabi]

Answer to Question 1

d

Answer to Question 2

b