The basic barometer can be used to measure the height of a building. If the barometric readings at the top and at the bottom of a building are 675 and 695 mmHg, respectively, Final PDF to printer cen22672_ch01_001-050.indd 42 11/03/17 07:10 AM 42 INTRODUCTION AND BASIC CONCEPTS determine the height of the building. Take the densities of air and mercury to be 1.18 kg/m3 and 13,600 kg/m3 , respectively.

230.4 m

Explanation:

Given

Pressure at the top of the barometer, P1 = 675 mmHg

Pressure at the bottom of the barometer, P2 = 695 mmHg

Density of air, ρ(air) = 1.18 kg/m³

Density of mercury, ρ(Hg) = 13600 kg/m³

P2 - P1 = 695 mmHg - 675 mmHg

P2 - P1 = 20 mmHg

(ρgh) of hg = 13600 * 9.81 * 20

(ρgh) of hg = 2668.3 Pa

P2 - P1 = ρ(air) * g * H, so that,

H = (P2 - P1) / ρ(air) * g

H = 2668.3 / 1.18 * 9.81

H = 2668.3 / 11.58

H = 230.4 m

quantum mechanics or quantum physics is physics of very small objects (particles) and physical entities.

quantum physics has some parallels to our macro world and some pretty unique ideas which theoretically and mathematically proven to be true even though we will never be able to access them because of our size.

there are many types of particles: subatomic, elementary etc.

subatomic means they are smaller than atom, elementary means they are at the very basis of everything.

subatomic particles are for eg. protons, neutrons but not electrons.

elementary particles are categorised into 3 groups by what they do.

these 3 groups are quarks, leptons and bosons.

light for example is a particle more precisely a photon a part of leptons.

proton (subatomic particle) is made out of 2 up quarks and 1 down quark each of these has a fractional charge like . (i crazy)

most famous scientist who contributed to this physics are:

the topic itself us understand a lot and will probably be vastly used in the future (quantum computers, understanding the big bang,

we also must not forget quantum effects like:

and there is more. but probably too much for this answer to be consistent due to my average understanding of this topic.

hope this you understand quantum mechanics a little more. i'm not an expert in the topic (so don't be like wth if you are an expert) but i'm very interested in it.

anyways quantum physics is a very hard topic (harder than physics (perhaps)) therefore searching for every information there is about it and learning it is unfortunately impossible (you can only specialise into 1 - 3 things or more (perhaps

have fun and i wish you luck!

r3t40

c. 7/3

step-by-step explanation:

a rational number is like pi- it is a repeating decimal.

a. is -1.8

b. 2.236068

c. 2.3333333333333333333

d.   is 3

i hope that ! =)