Question

question 41
which of the following are the most common forces acting on a human performer?
air pressure. gravity. ground reaction forces, air or water resistance
friction, gravity. ground reaction forces air or water resistance
friction, gravity. ground reaction forces, gas forces
heat, friction. gravity, air or water resistance

Explanation:

• Air pressure is not a force that directly affects a human performer's movement in the context of typical physical activities.
• Friction is important for movement (e.g., walking, running - shoes and ground interaction).
• Gravity is always acting on a human (pulling towards the Earth).
• Ground reaction forces are crucial (when a human exerts a force on the ground, the ground exerts an equal and opposite force - Newton's third law).
• Air or water resistance acts when a human is moving through air (e.g., running, jumping) or water (swimming).
• Gas forces is a rather vague and not a commonly - cited force in the context of human performance.
• Heat is not a force.

Answer:

friction, gravity, ground reaction forces, air or water resistance