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;

$M.A = \frac{L}{h}$

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

3 0

2 years ago

A typical person's eye is 2.5 cm in diameter and has a near point (the closest an object can be and still be seen in focus) of 2

Scrat [10]

Answer:

The minimum effective focal length of the focusing mechanism (lens plus cornea) of the typical eye is 2.27 cm.

Explanation:

The diameter of person's eye is 2.5 cm. The close point or the near point of the eye is 25 cm and the far point is infinity. We need to determine the minimum effective focal length of the focusing mechanism (lens plus cornea) of the typical eye. Let f is the minimum effective focal length. It can be calculated using lens formula as :

$\dfrac{1}{f}=\dfrac{1}{25}+\dfrac{1}{2.5}$

f = 2.27 cm

So, the minimum effective focal length of the focusing mechanism (lens plus cornea) of the typical eye is 2.27 cm and it is at the nearest point. Hence, this is the required solution.

6 0

2 years ago