It involves three masses, with mass 2 being the cart that can roll freely on a horizontal table. There is no friction anywhere. The cart system is let go with everything initially at rest. You are to find the accelerations for each of the three masses relative to the ground. (They are all different.)

This question does not make any sense, first of all you mention where 1 of the 3 masses are located also what is your force acting here? Is it a tension force acting on the freely rolling cart or the fact that the table is horizontal will do something here?

Post some more info or a picture if you can.

To find the accelerations for each of the three masses in the given scenario, we can use Newton's second law of motion, which states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

Let's break down the problem step by step:

1. Identify the masses and forces:
- Mass 1 (m1): The mass connected to mass 2 by a string.
- Mass 2 (m2): The cart that can freely roll on the horizontal table.
- Mass 3 (m3): The hanging mass that is connected to m1 by a string.
- Tension (T): The tension in the two strings connecting the masses.

2. Draw a free-body diagram for each mass:
- Mass 1 (m1): It experiences two forces: tension (T) pulling it to the right and its weight (m1 * g) pulling it downward.
- Mass 2 (m2): It experiences two forces: tension (T) pulling it to the left and its weight (m2 * g) pulling it downward.
- Mass 3 (m3): It experiences only one force, its weight (m3 * g), pulling it downward.

3. Write down the equations of motion for each mass:
- Mass 1 (m1): The net force acting on m1 in the horizontal direction is T (tension), and there are no forces acting on it vertically. Therefore, the equation becomes: T = m1 * a1 (where a1 is the acceleration of m1).
- Mass 2 (m2): The net force acting on m2 in the horizontal direction is T (tension), and there are no forces acting on it vertically. Therefore, the equation becomes: T = m2 * a2 (where a2 is the acceleration of m2).
- Mass 3 (m3): The net force acting on m3 is its weight (m3 * g) pulling it downward. Therefore, the equation becomes: m3 * g = m3 * a3 (where a3 is the acceleration of m3).

4. Solve the system of equations:
We have three equations with three unknowns (a1, a2, and a3). To solve them, we can use the following approach:
- Use equation 1 to express T in terms of a1: T = m1 * a1.
- Use equation 2 to express T in terms of a2: T = m2 * a2.
- Equate the two expressions for T: m1 * a1 = m2 * a2.
- Use equation 3 to express m3 * g in terms of a3: m3 * g = m3 * a3.
- We now have two equations with two unknowns (a1 and a3): m1 * a1 = m2 * a2 and m3 * g = m3 * a3. Solve this system of equations to find a1 and a3.
- Finally, use the obtained values of a1 and a3 to find a2 using equation 2.

By following these steps, you should be able to find the accelerations for each of the three masses relative to the ground in the given scenario.