Which of the following lists correctly identifies all the forces acting on a skydiver with an open parachute during steady descent?

• A. Gravitational force, normal force, and tension
• B. Air resistance ($\mathrm{drag}$) and friction
• C. Gravitational force and air resistance ($\mathrm{drag}$)
• D. Gravitational force and magnetic force

Answer: (C)

Verified step by step guidance

1. Step 1: Identify the forces acting on the skydiver during steady descent. The main forces to consider are those that influence vertical motion: gravity pulling downward and air resistance (drag) pushing upward.
2. Step 2: Understand that the gravitational force is the weight of the skydiver, given by \(F_{gravity} = m \times g\), where \(m\) is mass and \(g\) is acceleration due to gravity.
3. Step 3: Recognize that air resistance (drag) acts opposite to the direction of motion and increases with speed until it balances the gravitational force, resulting in steady descent (constant velocity).
4. Step 4: Note that normal force does not act here because the skydiver is not in contact with a solid surface, and tension is not present unless there is a rope or cable, which is not the case.
5. Step 5: Conclude that the only forces acting on the skydiver during steady descent with an open parachute are gravitational force downward and air resistance (drag) upward.