The main reason why wheelchair ramps are used to move people up a staircase is because it has a high mechanical advantage which leads to a greater efficiency in moving people up the staircase.
- <em>Let the height of the staircase = h</em>
- <em>Let the length of the ramp = L</em>
The mechanical advantage of the ramp is calculated as follows;

As the length of the ramp increases, people will be move up to a greater distance up the staircase.
Thus, the main reason why wheelchair ramps are used to move people up a staircase is because it has a high mechanical advantage which leads to a greater efficiency in moving people up the staircase.
Learn more about mechanical advantages of ramps here: brainly.com/question/200179
Answer:
glass is optically denser as it is a optical material having more index number above the list
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Explanation:</u></h2>
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<h3>Potential:</h3>
- This refers to an object having energy running through it, but being stored. It hasn't quite been released yet.
- Ex: <em>Someone waiting to dive into a pool, when a whistle blows.</em>
<h3 /><h3>Kinetic: </h3>
- This refers to the energy going through an object but that energy is moving, it's been released.
- Ex: <em>A boy pedaling his bike atop a hill. </em>
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Explanation:
It is (Harder/easier) to push an empty wheelbarrow than one filled with dirt. Because the dirt-filled wheelbarrow has more (Force/Speed/Mass) than the empty one, it requires more (Force/Inertia/Acceleration) to push at the same speed. A wheelbarrow containing grass clippings will require (More/Less/The Same) force to push at the same speed than a dirt-filled one because the grass clippings have less mass than dirt. Either wheelbarrow will require more force to push it uphill than downhill due to the effect of (Friction/Inertia)