What is potential energy?

Energy stored in an object due to its position.

What are conservative forces?

Forces that conserve mechanical energy.

Increases mechanical advantage without reducing work done.

Total energy in a system remains constant.

Friction decreases total mechanical energy.

Gravitational potential energy is directly related to an object's height above the ground, changing as the height changes, impacting the work done when lifting or lowering the object.
The presence of non-conservative forces like friction can lead to a decrease in the total mechanical energy of a system, affecting the speed and energy levels of objects within that system, highlighting the importance of considering all forces in energy conservation problems.

What is potential energy?
Energy stored in an object due to its position.
What are conservative forces?
Forces that conserve mechanical energy.
How does a ramp affect lifting objects?
Increases mechanical advantage without reducing work done.
What is conservation of mechanical energy?
Total energy in a system remains constant.
How does friction impact energy conservation?
Friction decreases total mechanical energy.

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Chapter 7 discusses potential energy and energy conservation, introducing gravitational potential energy related to vertical motion and elastic potential energy related to springs.
Two types of forces are introduced: conservative forces and non-conservative forces, impacting work and energy in problem-solving.
Gravitational potential energy is defined as mass * gravity * height, with height measured from the ground.
Lifting an object increases its gravitational potential energy, while lowering it decreases this energy.
Work done lifting an object equals the gravitational potential energy gained, calculated as mass * gravity * height.
Using a ramp to lift an object showcases mechanical advantage, affecting force and distance but not reducing the work done.
Conservation of mechanical energy states that the total energy in a system remains constant, comprising kinetic and potential energy.
A long jumper's energy at different points must remain constant, balancing kinetic and potential energy changes.
When non-gravitational forces like friction are involved, the total mechanical energy of a system is not constant.
Work and energy along a curved path can be simplified by focusing on gravitational potential energy, unaffected by the path taken.

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Frictional force acts in the opposite direction of the boy's displacement on the ramp, reducing his kinetic energy as he descends.
The presence of friction decreases the total energy of the system, leading to a reduction in gravitational potential energy and a slower speed at the bottom of the ramp.
The work done by friction on the box going up and down the ramp results in a decrease in the total energy of the system, impacting the speed and energy levels of the box at different points along the ramp.