Final answer:
a) The acceleration of the system is 1.92 m/s². c) The gravitational force acting on the boxes is 12.74 N. d) The net force acting on the system is -5.24 N.
Step-by-step explanation:
a) To find the acceleration of the system, we can use Newton's second law, which states that the force acting on an object is equal to the mass of the object multiplied by its acceleration. In this case, the force applied is 7.5 N and the mass of the system is the sum of the masses of the three boxes (m1 = 1.3 kg). So, the acceleration can be calculated as follows:
Force = mass x acceleration
7.5 N = (1.3 kg + 1.3 kg + 1.3 kg) x acceleration
acceleration = 7.5 N / 3.9 kg = 1.92 m/s²
b) To determine the velocity of the boxes, we need to know the time over which the force is applied. Without this information, we cannot calculate the velocity.
c) The gravitational force acting on the boxes can be calculated using the equation F = mg, where F is the force, m is the mass, and g is the acceleration due to gravity (approximately 9.8 m/s² on Earth). For each box, the gravitational force is:
F = (1.3 kg x 9.8 m/s²) = 12.74 N
d) The net force acting on the system is equal to the applied force (7.5 N) minus the gravitational force acting on the boxes (12.74 N). Since the applied force is less than the gravitational force, the net force is negative:
Net force = 7.5 N - 12.74 N = -5.24 N