Answer:
Since steel contains iron (a magnetic metal), the magnets will attract the steel cans since aluminum is not magnetic. This is used to separate the steel cans from the aluminum cans so they can be recycled separately.
Answer:
(a) 89 m/s
(b) 11000 N
Explanation:
Note that answers are given to 2 significant figures which is what we have in the values in the question.
(a) Speed is given by the ratio of distance to time. In the question, the time given was the time it took the pulse to travel the length of the cable twice. Thus, the distance travelled is twice the length of the cable.

(b) The tension,
, is given by

where
is the speed,
is the tension and
is the mass per unit length.
Hence,

To determine
, we need to know the mass of the cable. We use the density formula:

where
is the mass and
is the volume.

If the length is denoted by
, then


The density of steel = 8050 kg/m3
The cable is approximately a cylinder with diameter 1.5 cm and length or height of 620 m. Its volume is




Answer:
atom -
the smallest particle of a chemical element that can exist.
atomic mass-
the quantity of matter contained in an atom of an element
atomic weight -
ratio of the average mass of a chemical element's atoms to some standard
protons-
stable subatomic particle that has a positive charge equal in magnitude to a unit of electron charge and a rest mass of 1.67262 × 10−27 kg
electrons-
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids
neutrons-
a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
energy levels-
one of the stable states of constant energy that may be assumed by a physical system
[used especially of the quantum states of electrons in atoms and of nuclei. — called also energy state.]
Covalent bonds
the interatomic linkage that results from the sharing of an electron pair between two atoms.
ionic bonds
type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound.
Valence electrons
a single electron or one of two or more electrons in the outer shell of an atom that is responsible for the chemical properties of the atom.
Lewis Dot Diagram
A way of representing atoms or molecules by showing electrons as dots surrounding the element symbol. One bond is represented as two electrons.
Answer:
We have a not significant increase of the population until 1700s or 1800s and then a significant increase growth from these years to the present.
Explanation:
From the figure attached we see the evolution of the human population since early times (1050).
We see that from 1050 until 1750-1850 we have an increase slowly with a low value for the increase per year.
But after these years (1750-1850) we see a considerable increase of the population, like an exponential model.
So then we can conclude in general terms this:
We have a not significant increase of the population until 1700s or 1800s and then a significant increase growth from these years to the present.
Answer:
mass = 9.7 kg
Explanation:
As we know that when object is at rest on the ground of flat base then we will have

so from here

now we have
N = 95 Newton
now from above equation we will have


