All categories

2 years ago

When the cornea and lens of the eye do not properly focus

Physics

1 answer:

frutty [35]2 years ago

3 0

Answer:

When there is nearsightedness or myopia

Explanation:

As, in myopia the image is formed in front of the retina.

Which makes things looking at things near very easy, but looking at far away things very difficult.

So concave lens makes things look bigger, so therefore, it is used during myopia, to make things look bigger when they are far away

You might be interested in

If the load distance of a lever is 30 cm and the effort distance is 60 cm, calculate the amount of effort required to lift a loa

vladimir2022 [97]

Here,

Load distance (Ld) = 30 cm

Effort distance (Ed) = 60 cm

Load (L) = 200N

Effort (E) = ?

Now, By using formula,

or, E * Ed = L * Ld

or, E * 60 = 200 * 30

or, E = 6000/60

◆ E = 100N

This is a Right answer...

I hope you understand...

7 0

2 years ago

What is the mass of an object with a density of 18 g/cm3 and a volume of 25 cm3

DiKsa [7]

Answer: 0.72 grams

Explanation: Mass can be extracted from the formula of density. D=M/V where D is density and V is volume. Therefore:

18 g/cm^3 = M(25 cm^3) --> Divide by 18g/cm^3 by 25 cm^3 to isolate mass. --> 0.72 =M --> Now, to find out which unit you need to use for mass, just look at the density. You can see it is in g/cm^3, and cm^3 was already used for the volume. Thus, gram units are left, so that will be the unit needed, making the final answer 0.72 grams. Hope this helps :)

5 0

1 year ago

Assignment 10 Coulombic Equation Practice Directions: Complete the following problems to calculate the electrostatic force that

Tatiana [17]

Answer:

Magnitude of the force between the charges is F = 1.92×10^20N

Explanation:

Given the magnitude of force according to coulombs law

F =K[(q1*q2)/r2]

Where q1 and q2 are the charges

r is the distance between the charges

K is the coulombs constant

Substituting the given values, we have;

F = 8.98×10^9 × 1.5×10^6 × 3.2×10^4/1.5²

F = 43.1×10^19/2.25

F = 19.16×10^19N

F = 1.92×10^20N

8 0

2 years ago

A 13.0-g wad of sticky clay is hurled horizontally at a 110-g wooden block initially at rest on a horizontal surface. The clay s

Alisiya [41]

Answer:

$v_{ic}=92.53 m/s$

Explanation:

We need to apply conservation of momentum and energy to solve this problem.

Conservation of momentum

$p_{i}=p_{f}$

$m_{c}v_{ic}=(m_{c}+m_{w})V$ (1)

m(c) is the mass of stick clay
m(w) is the mass of the wooden block
v(ic) is the initial velocity of clay
V is the final velocity of the system clay plus wood.

Conservation of total energy

The change in kinetic energy is equal to the change in internal energy, in our case it would be the energy loss due to the friction force. Let's recall the definition of work, it is the dot product between force and displacement, Therefore:

$\Delta E=W$

$\frac{1}{2}(m_{c}+m_{w})V^{2}=F_{friction}*d$

$\frac{1}{2}(m_{c}+m_{w})V^{2}=\mu (m_{c}+m_{w})gd$

We can find V from this equation:

$V=\sqrt{2\mu gd}=\sqrt{2*0.65*9.81*7.5}=9.78 m/s$

Now, let's put V into the equation (1) and find v(ic)

$v_{ic}=\frac{(m_{c}+m_{w})V}{m_{c}}=\frac{123*9.78}{13}=92.53 m/s$

I hope it helps you!

8 0

2 years ago

If element x has 44 protons how many electrons does it have?

Jlenok [28]

The correct answer is '44'.

In fact, the atom of an element has an equal number of protons and electrons: therefore, if element X has 44 protons, it should have 44 electrons as well.

For curiosity: the chemical element with 44 protons and 33 electrons is Ruthenium.

5 0

3 years ago