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3 years ago

A person can see clearly up close but cannot focus on objects beyond 75.0 cm. She opts for contact lenses to correct her vision.

Physics

1 answer:

Pavel [41]3 years ago

7 0

Answer:

(a) nearsighted

(b) diverging

(c) the lens strength in diopters is 1.33 D, and considering the convention for divergent lenses normally prescribed as: -1 33 D

Explanation:

(a) The person is nearsighted because he/she cannot see objects at distances larger than 75 cm.

(b) the type of correcting lens has to be such that it counteracts the excessive converging power of the eye of the person, so the lens has to be diverging (which by the way carries by convention a negative focal length)

$f=\frac{1}{d} =\frac{1}{0.75} = 1.33\,D$

So it would normally be written with a negative signs in front indicating a divergent lens.

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Trial 1: Get a textbook and put a sheet of paper on top of it. Fold the paper as needed to keep the paper from sticking over the

siniylev [52]

Answer:

1) the two objects reach the floor at the same time.

2)the book reaches the floor much earlier than the foil

In conclusion, the difference in motion between the two systems subjected to the same acceleration depends on the weight of the body and friction force, when the body has less weight, the friction of the air affects it more

Explanation:

This interesting experiment has the following results

1) first case. Sheet on top of book

In this case the two objects reach the floor at the same time.

This shows that the acceleration in the two objects is the same and we call it the acceleration of gravity.

The speed of the body increases as it goes down linearly.

This occurs because the book that receives air resistance is much heavier, so the resistance has almost no effect on its movement, the sheet does not have the air resistance because it goes down next to the book.

2) second case. Book and sheet next to each other.

In this case the book reaches the floor much earlier than the foil.

This is because the resisting force of the air has almost no effect on the book and its movement is little affected by this force.

In the case of the blade, it has very little weight, therefore as its speed increases, the resistance force of the air rapidly equals the weight of the blade.

W_sheet - fr = 0

so after this, since the acceleration is zero, it goes down at constant speed, this speed is called the terminal velocity.

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3 years ago

According to the "Law of Increasing Opportunity Costs," what would be the opportunity cost of a student who is staying up all ni

kodGreya [7K]

C. The opportunity cost of a student who is staying up all night to study for an exam that he has to take in the early morning is sleep or rest.

<h3>What is law of opportunity cost?</h3>

The law of increasing opportunity cost is an economic principle that describes how opportunity costs increase as resources are applied.

As the student gives up his sleep or night rest in the place of his exam preparation, we say that the opportunity cost is the sleep or rest.

Thus, the opportunity cost of a student who is staying up all night to study for an exam that he has to take in the early morning is sleep or rest.

Learn more about opportunity cost here: brainly.com/question/8846809

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2 years ago

An object has a mass of 12 kg. on planet a, the object weighs 69 n. the force of gravity on planet a is:_____.

balandron [24]

the force of gravity on planet a is g = 5.72 m/s2

There is an object that weighs 12 kg. The object's weight on Planet A is 69 N. The equation F=mg, where F is the weight, m is the mass, and g is the force of gravity, can be used to calculate the force of gravity on Planet A:

g = F/m

g = 69 N/ 12 kg

g = 5.72 m/s2

<h3>What is the gravity force?</h3>

The force of attraction between any two objects in the universe is known as gravity or gravitational force. The mass of the object and the square of the distance between them determine the force of attraction. The weakest known force in nature, it is by far.

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2 years ago

Select all the correct answers.

Rus_ich [418]

It's density increases

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3 years ago

Read 2 more answers

What is the force between two proton’s that are 0.005m apart?

Jet001 [13]

Answer:

Force, $F=9.21\times 10^{-24}\ N$

Explanation:

Distance between proton is 0.005 m

It is required to find the force between two protons. Protons have of positive charge of $1.6\times 10^{-19}\ C$ . Two protons will have a force of repulsion between them. The force is given by :

$F=\dfrac{kq^2}{r^2}\\\\F=\dfrac{9\times 10^9\times (1.6\times 10^{-19})^2}{(0.005)^2}\\\\F=9.21\times 10^{-24}\ N$

So, the force between two protons is $9.21\times 10^{-24}\ N$ .

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4 years ago