EjerciciosFyQ

Types of forces: at a distance or through contact (4841)

F_y_Q — 2020-02-04T06:23:54Z

Indicate which of these phenomena are produced by forces at a distance and which are produced by forces through contact:
a) The motion of a train due to magnetic levitation.
b) The deformation of a spring when a weight is attached to it.
c) The skidding of a car on a pool of water.
d) The formation of the aurora borealis.
e) The motion of a cupboard when pushed.

- Forces and their effects / RESUELTO, INGLÉS, Bilingüismo

Classifying into laws and theories

F_y_Q — 2019-12-25T06:22:10Z

Classify the next examples as laws or theories, considering the definition of each one.
a) When the temperature rises, will be simpler to dissolve a solid into the water.
b) The global warming is due to the excessive emissions of carbon dioxide, and other gases, to the atmosphere and it is the cause of many changes in the climates of the Earth.
c) In a chemical reaction, the total mass of the initial substances is equal to the total mass of the final substances.
d) A chemical reaction implies that substances change their composition and they have to be converted from one to other different substances by the combination of their atoms.

To solve this exercise you must remember that laws describe what will happen in a determine situation or condition, while theories explain how occurs the facts and they have been exhaustively shown by the scientific community.
a) It is a law.
b) It is a theory.
c) It is a law.
d) It is a theory.

Classification of bodies: rigid, elastic or plastic (4842)

F_y_Q — 2019-11-11T18:42:02Z

Classify the following objects into rigid, plastic or elastic bodies:
a) The mechanism of a key on the computer keyboard.
b) Sunglasses.
c) A headband.
d) A steel fork.
e) The bristles of a toothbrush.
f) Bread dough.

- Forces and their effects / RESUELTO, INGLÉS, Bilingüismo

Will do float silver over mercury?

F_y_Q — 2019-01-03T08:12:31Z

Imagine that you heat a system with upper temperatures than the fusion points of silver and mercury. If you put in contact both substances, will do silver float over mercury? Look for the information that you need on the Internet and explain your answer.

The fluids, remember that silver and mercury will be in the liquid state, they will order their positions according to the value of their densities, the higher the density, the lower the position.
Looking for the density data for mercury and silver, we obtain: and . Silver will float over the mercury because its density is smaller than the density of mercury.

Volume occupied by a known mass of mercury

F_y_Q — 2019-01-03T07:42:10Z

The density of mercury is 13.6 g/mL. What will be the volume of 25 000 g of mercury?

Using the density datum as a conversion factor, you can obtain the volume if you multiply the mass of mercury by the density:

Mass of a piece of marble knowing its density and volume

F_y_Q — 2019-01-03T07:09:26Z

What will be the mass of a piece of marble that occupies volume, if its density is ?

A simple way to do this exercise is using the density equation: .
If you clear mass from the equation, you can obtain the value of mass:

Convertion of units: speed of a car (3600)

F_y_Q — 2016-06-08T07:06:40Z

A car is moving in a straight path, covering 3 600 meters in 90 seconds. Determine the speed of the car, expressed in km/h.

We are going to use the velocity equation and two conversion factors:

Acceleration of a car (3583)

F_y_Q — 2016-05-22T06:35:14Z

A car is increasing its speed from 40 m/s to 70 m/s. What is its acceleration if the time needed was 3 seconds?

Acceleration is defined by:

Replace the problem data:

Descarga el enunciado y la resolución del problema en formato EDICO si lo necesitas.

Time taken to cover a distance by car (3567)

F_y_Q — 2016-05-06T04:55:51Z

If the speed of a car is 75 km/h. How long does it take the car to cover a distance of 75 km?

Using the definition of speed:

Rearranging the formula to solve for time:

Substituting the given values:

Descarga el enunciado y la resolución del problema en formato EDICO si lo necesitas.

Time it takes for blood to cover 30 cm distance (3494)

F_y_Q — 2016-02-23T05:08:46Z

The speed of blood flow is 30 cm/s. Considering a vein as a straight path, how long will it take for blood to cover a distance of 30 cm?

Speed is the quotient between distance and time. To find the time, you use the fomula:

Descarga el enunciado y la resolución del problema en formato EDICO si lo necesitas.