Final answer:
Both carts exert an equal force of 600 N, which are balanced since they are equal in magnitude and opposite in direction. The first cart achieves this force by accelerating to 60 m/s over 4 seconds, and the second cart is accelerating at 20 m/s².
Step-by-step explanation:
The question asks which of the two carts would have a greater force upon collision and whether the forces are balanced or unbalanced. To find the force each cart exerts during collision, we can use the formula F = ma, where F is force, m is mass, and a is acceleration.
For the first cart, we have an initial speed of 0 m/s, a final speed of 60 m/s, and a time of 4 seconds. Using the formula a = (∆v / ∆t), the acceleration is (60 - 0) / 4 = 15 m/s². So the force for the first cart is F = ma = 40 kg × 15 m/s² = 600 N.
The second cart is accelerating at 20 m/s² and has a mass of 30 kg. Therefore, the force for the second cart is F = ma = 30 kg × 20 m/s² = 600 N.
Both carts would exert the same amount of force upon collision, 600 N, assuming they collide at the moment when the first cart reached its final speed and while the second cart is still accelerating. Because the forces are equal in magnitude and opposite in direction, they are balanced, and no net force should act on the system of the two carts combined at the moment of collision.