All categories

3 years ago

1. The nearest distance of distinct vision of

Physics

1 answer:

Vedmedyk [2.9K]3 years ago

3 0

Answer:

The focal length of the lens is +30 and it is a convex lens.

Explanation:

Given that,

The nearest distance of distinct vision of a hypermetropial person is 60 cm, v = -60 cm

The distance is reduced by 20 cm, u = -20 cm

We need to find the nature and focal length of the lens.

Let f be the focal length of the lens. Using lens formula,

$\dfrac{1}{v}-\dfrac{1}{u}=\dfrac{1}{f}\\\\\dfrac{1}{f}=\dfrac{1}{(-60)}-\dfrac{1}{(-20)}\\\\f=+30\ cm$

So, the focal length of the lens is +30 and it is a convex lens.

You might be interested in

Which group of types of light is listed in order of increasing frequency? which group of types of light is listed in order of in

never [62]

Your answer is infrared, visible, ultraviolet.

6 0

3 years ago

One difference between a hypothesis and a theory is that a hypothesis

artcher [175]

A hypothesis is a tentative statement which is made to try to explain a known phenomenon but whose truth value is still uncertain, whether it is true or no depends on further research. On the other hand, a theory is made up of hypothesis which have been proven to be true so far, a theory should be able to explain future phenomena successfully

3 0

3 years ago

The vapor pressure of diethyl ether (ether) is 463.57 mm Hg at 25°C. How many grams of chlorophyll, C55H72MgN4O5, a nonvolatile,

mixer [17]

Answer:

29.4855 grams of chlorophyll

Explanation:

From Raoult's law

Mole fraction of solvent = vapor pressure of solution ÷ vapor pressure of solvent = 457.45 mmHg ÷ 463.57 mmHg = 0.987

Mass of solvent (diethyl ether) = 187.4 g

MW of diethyl ether (C2H5OC2H5) = 74 g/mol

Number of moles of solvent = mass/MW = 187.4/74 = 2.532 mol

Let the moles of solute (chlorophyll) be y

Total moles of solution = moles of solute + moles of solvent = (y + 2.532) mol

Mole fraction of solvent = moles of solvent/total moles of solution

0.987 = 2.532/(y + 2.532)

y + 2.532 = 2.532/0.987

y + 2.532 = 2.565

y = 2.565 - 2.532 = 0.033

Moles of solute (chlorophyll) = 0.033 mol

Mass of chlorophyll = moles of chlorophyll × MW = 0.033 × 893.5 = 29.4855 grams

8 0

3 years ago

Your roommate drops your wallet down to you from the third-floor window of your apartment, which is 11.5 m from the ground. What

Aneli [31]

Answer:

15 m/s

Explanation:

Using the law of conservation of energy, potential energy equals kinetic energy hence

$mgh=0.5mv^{2}$

Therefore

$v=\sqrt{2gh}$

where g is the acceleration due to gravity, m is the mass of the object, h is the height and v is the speed of the wallet

Taking g as 9.81 then

$v=\sqrt{2\times 9.8\times 11.5}=15.02098532 m/s\approx 15 m/s$

6 0

3 years ago

Interactions of current carrying wires

koban [17]

Physics stack exchange

7 0

3 years ago