A baby carriage is sitting at the top of a hill that is 21 m high The carriage with the baby weighs 12 N

E

=

252

J

Explanation:

The total mechanical energy of an object or system is given by:

E

m

e

c

h

=

K

+

U

Where

K

is the kinetic energy of the object and

U

is the potential energy of the object. The carriage, sitting motionless at the top of the hill, has only potential energy in the form of gravitational potential energy.

Gravitational potential energy is given by:

U

g

=

m

g

h

Where

m

is the mass of the object,

g

is the gravitational acceleration constant, and

h

is the height of the object above some specific reference point, in this case the ground

21

m

below.

The weight of a stationary object at the surface of the earth is equal to the force of gravity acting on the object.

W

=

→

F

g

=

m

g

We are given that the carriage weighs

12

N

, therefore

m

g

=

12

N

.

U

g

=

12

N

⋅

21

m

⇒

U

g

=

252

N

m

=

252

J

Answer link

Explanation:

specific latent heat of fusion, lf, of a substance is defined as the amount of heat required to change a unit mass of the substance from solid to liquid state, without any change in the temperature.

explanation:

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