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vlabodo [156]
2 years ago
10

He lens of the eye loses its ________ with age, which impairs the ability to focus.

Physics
1 answer:
Rom4ik [11]2 years ago
7 0

The lens of the eye loses its <u>flexibility</u> with age, which impairs the ability of the eyes to focus. This process is called presbyopia.

Presbyopia happens when the lens of the eye loses its flexibility due to age. The lens of the eye works similar to the lens of a digital camera. The digital camera focuses on objects that are far or near by by adjusting the placement of the lens, by slightly moving it forward or backward, constantly changing its focal length. The human eye does the same, but instead of moving the lens, the lens changes its shape to focus on far or near objects, thereby also changing its focal length. This is also called accommodation.

To focus on far objects, certain muscles around the lens relax, making the lens rounder in shape, while for close objects, the muscles contract, making the lens flatter in shape.

As a person ages, the lens thickens and gradually loses its flexibility, and around the age of 40, the lens is no longer flexible. Therefore, it becomes difficult to focus on close objects. This condition is therefore known as presbyopia.

To learn more about how the human eye functions, check out;

brainly.com/question/16834488

#SPJ4

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18.5 miles per second (30 km/sec). Choose the Earth movement that best relates to this description.
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Answer:

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Explanation:

6 0
3 years ago
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Two forces act on an object. The first force has a magnitude of 17.0 N and is oriented 48.0° counterclockwise from the x ‑axis,
Ivanshal [37]

Answer:

Fn: magnitude of the net force.

Fn=30.11N , oriented 75.3 ° clockwise from the -x axis

Explanation:

Components on the x-y axes of the 17 N force(F₁)

F₁x=17*cos48°= 11.38N

F₁y=17*sin48° = 12.63 N

Components on the x-y axes of the  the second force(F₂)

F₂x= −19.0 N

F₂y=   16.5 N

Components on the x-y axes of the net force (Fn)

Fnx= F₁x +F₂x= 11.38N−19.0 N= -7.62 N

Fny= F₁y +F₂y= 12.63 N +16.5 N = 29.13 N

Magnitude of the net force.

F_{n} =\sqrt{(F_{nx})^{2} +(F_{ny}) ^{2} }

F_{n} =\sqrt{(-7.62)^{2} +(29.13) ^{2} }

F_{n} = 30.11N

Direction of the net force (β)

\beta =tan^{-1} (\frac{29.13}{7.62} )

β=75.3°

Magnitude and direction of the net force

Fn= 30.11N , oriented 75.3 ° clockwise from the -x axis

In the attached graph we can observe the magnitude and direction of the net force

6 0
3 years ago
A sphere has surface area 1.25 m2, emissivity 1.0, and temperature 100.0°C. What is the rate at which it radiates heat into empt
Yuri [45]
The total power emitted by an object via radiation is:
P=A\epsilon \sigma T^4
where:
A is the surface of the object (in our problem, A=1.25 m^2
\epsilon is the emissivity of the object (in our problem, \epsilon=1)
\sigma = 5.67 \cdot 10^{-8} W/(m^2 K^4) is the Stefan-Boltzmann constant
T is the absolute temperature of the object, which in our case is T=100^{\circ} C=373 K

Substituting these values, we find the power emitted by radiation:
P=(1.25 m^2)(1.0)(5.67 \cdot 10^{-8}W/(m^2K^4)})(373 K)^4=1371 W = 1.4 kW
So, the correct answer is D.
6 0
3 years ago
Using equations, determine the temperature, pressure and density of the air for a aircraft flying at 19.5 km. Is this aircraft s
Viefleur [7K]

Answer:

a) - 72.5°c

b) pressure = 3625.13 Pa

c) density =  0.063 kg/m^3

d) it is a subsonic aircraft

Explanation:

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Temperature at 19.5 km ( 19500 m )

T = -131 + ( 0.003 * altitude in meters )

  =  -131 + ( 0.003 * 19500 ) = - 72.5°c

b) Determine pressure and density at 19.5 km altitude

Given :

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pressure = 3625.13 Pa

hence density = 0.063 kg/m^3

attached below is the remaining part of the solution

C) determine if the aircraft is subsonic or super sonic

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hence it is a subsonic aircraft

4 0
3 years ago
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alukav5142 [94]
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Hope this helps! :)
7 0
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