Final answer:
The acceleration parallel to an incline with 45.0 N of opposing friction cannot be calculated without the mass of the object. With only the gravitational component, the acceleration would be 9.8 m/s², but the net force and thus the actual acceleration depend on the object's mass.
Step-by-step explanation:
To calculate the acceleration parallel to the incline when there is 45.0 N of opposing friction, we need to consider both the gravitational force component down the incline and the frictional force. If the incline angle is 45 degrees, the gravitational component (for a mass m) down the incline would be mg sin(θ), where g is the acceleration due to gravity and θ is the angle of the incline. If we assume g to be approximately 9.8 m/s², and that mass and gravitational force are equivalent for this example (ignoring the units discrepancy for simplicity), then the component of the gravitational force parallel to the incline would be 9.8 N (since sin(45 degrees) = 0.7071, and 9.8*0.7071 ≈ 9.8).
The net force acting down the incline would be the gravitational component minus the frictional force, which is 9.8 N - 45.0 N = -35.2 N. This would indicate that the frictional force exceeds the gravitational component and thus, the object would not accelerate further down the incline once in motion, but rather decelerate, or it would not start moving if it was at rest.
However, if we assume that the question is asking for the acceleration value prior to applying the frictional force, it would be 9.8 m/s² down the slope due to gravity alone. Yet, with the 45.0 N of friction factored in, the actual acceleration cannot be determined without knowing the mass of the object, as a = F/m, where F is the net force and m is the mass. To provide an accurate acceleration value, more information is needed.