Final answer:
The assertion that suspension training is an open kinetic chain is false; suspension exercises typically involve a closed kinetic chain. Additionally, true statements for physics principles include the increase of potential energy when going uphill on a bicycle.
Step-by-step explanation:
The statement that suspension training exercises are an open kinetic chain is false. Open kinetic chain exercises are characterized by the movement of the limb where the hand or foot is not fixed to an object and is freely moving in space. In contrast, closed kinetic chain exercises involve movements where the hand or foot is stationary and fixed to an object, like the ground or a solid surface.
Regarding the physics questions:
- While riding a bicycle up a gentle hill, it is true that it is fairly easy to increase your potential energy, as you are moving against gravity, but increasing your kinetic energy would take more effort and could make you feel exhausted.
- If a rock is thrown into the air, the statement is false. The increase in height increases the rock's potential energy, while the increase in velocity as it falls to the ground increases its kinetic energy.
- It is true that kinetic friction is generally less than the limiting static friction because once an object is moving, there are usually fewer points of contact, and so the friction is reduced. More force is typically required to start moving an object than to keep it in motion, due to static friction being higher than kinetic friction.