Final answer:
To calculate the net force on the rock, subtract the air resistance from the force of gravity, resulting in a net force of 26.4 N acting downward on the rock.
Step-by-step explanation:
The student asked, "What is the net force acting on the rock if a 3-kg rock falls from a cliff and encounters a 3-N air resistance?" To find the net force (Fnet) acting on the rock, we need to consider the force of gravity acting on the rock as well as the opposing air resistance. The force of gravity (Fgravity) can be calculated using the equation Fgravity = mg, where m is the mass of the rock and g is the acceleration due to gravity (9.8 m/s2). For a 3-kg rock, Fgravity = 3 kg × 9.8 m/s2 = 29.4 N. Subtracting the air resistance force (Fair = 3 N) from the force of gravity gives us the net force: Fnet = Fgravity - Fair = 29.4 N - 3 N = 26.4 N. Since the options provided do not include 26.4 N, and the question may contain a typo or error, we refrain from selecting any of the given options. It's important always to apply the correct formulas and check calculations to ensure accuracy.