Final answer:
The result of the equation Fthrust + (-) Fair + (-) Fgravity depends on the comparative magnitudes of the thrust, air resistance, and gravitational forces, determining whether the net force is positive, negative, or zero.
Step-by-step explanation:
The result of the equation Fthrust + (-) Fair + (-) Fgravity will depend on the magnitudes of these three forces. In a situation where a sled is accelerating to the right, for example, only horizontal forces are considered because vertical forces cancel out, assuming there is no vertical acceleration. The thrust force (Fthrust) is the force propelling an object forward, while air resistance (Fair) and gravity (Fgravity) typically oppose the motion.
If Fthrust is greater than the sum of Fair and Fgravity, the resultant force will be positive, indicating an acceleration to the right. If Fthrust is less, the resultant force will be negative, indicating deceleration. If all forces balance out perfectly, the result would be zero, implying no acceleration.
Newton's second law, which states that ΣF=ma, supports this approach by considering the net force acting on a body. However, without specific values for these forces, we cannot determine the exact result numerically, but we can infer the direction of the net force based on which forces are greater.