Answer:
Respuesta correcta, opción D: Es la fuerza que un cuerpo ejerce perpendicularmente sobre el área en la que actúa.
Explanation:
La definición de presión es la fuerza que un cuerpo ejerce en dirección perpendicular sobre el área en la que actúa.
Cuando se aplica una fuerza sobre la superficie de un cuerpo, la presión es la siguiente:

En donde:
F es la fuerza aplicada.
A es el área del cuerpo.
Por lo tanto la opción correcta es la D: es la fuerza que un cuerpo ejerce perpendicularmente sobre el área en la que actúa.
Espero que se sea de utilidad!
Answer:
c. vf is greator than v2, but less than v1
Explanation:
The principle of conservation of linear momentum states that when two or more bodies act upon one another, their total momentum remains constant.
In a system of colliding bodies the total momentum of the system just before the collision is the same as the total momentum just after the collision.
Collisions in which the kinetic energy is conserved are called elastic collision.
Collisions in which the kinetic energy is not conserved are called inelastic collisions. If the two objects stick together after the collision and move with a common velocity, the collision is said to be perfectly inelastic.
<em>The above scenario is a perfectly inelastic collision. The initial velocity of particle 1 was greater than particle 2 before collision. After collision, its velocity will reduce to a final velocity vf as it transfers some of its kinetic energy to particle 2; whereas, the velocity of particle 2 will increase to a final velocity vf as it absorbs some of the kinetic energy of particle 1.</em>
Therefore,
a. vf = v2 is wrong because vf is greater than v2
b. vf is less than v2 is wrong because vf is greater than v2
c. vf is greater than v2, but less than v1 is correct.
d. vf = v1 is wrong because vf is less than v1
Answer:
Components: 0.0057, -0.0068. Magnitude: 0.0089 m/s
Explanation:
The displacement in the x-direction is:

While the displacement in the y-direction is:

The time taken is t = 304 s.
So the components of the average velocity are:


And the magnitude of the average velocity is

Answer:
Approximately
.
Explanation:
This question suggests that the rotation of this object slows down "uniformly". Therefore, the angular acceleration of this object should be constant and smaller than zero.
This question does not provide any information about the time required for the rotation of this object to come to a stop. In linear motions with a constant acceleration, there's an SUVAT equation that does not involve time:
,
where
is the final velocity of the moving object,
is the initial velocity of the moving object,
is the (linear) acceleration of the moving object, and
is the (linear) displacement of the object while its velocity changed from
to
.
The angular analogue of that equation will be:
, where
and
are the initial and final angular velocity of the rotating object,
is the angular acceleration of the moving object, and
is the angular displacement of the object while its angular velocity changed from
to
.
For this object:
, whereas
.
The question is asking for an angular acceleration with the unit
. However, the angular displacement from the question is described with the number of revolutions. Convert that to radians:
.
Rearrange the equation
and solve for
:
.
Answer:
43.41 mm
Explanation:
Given:
thickness of sheet, t = 6 mm
Force exerted by punch, F = 45 KN
Average shearing stress, T = 55 MPa
From average shearing stress T = Force F / Area A
Hence area = force/stress =45000/ 55 =
From area = pi*diameter*thickness
diameter = area/(pi* thickness)
= 818.18/(3.142*6)
= 43.41 mm