Force for constant mass

Storyboard

If the mass of the object remains constant, the moment of inertia depends solely on the velocity, making the definition of force proportional to the change in velocity over time. Since this change corresponds to acceleration, the force in this case becomes proportional to it, allowing for the direct calculation of the object's dynamics.

>Model

ID:(2084, 0)



Force case constant mass

Equation

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In the case where the inertial Mass ($m_i$) equals the initial mass ($m_0$),

$ m_g = m_i $



the derivative of momentum will be equal to the mass multiplied by the derivative of the speed ($v$). Since the derivative of velocity is the instant acceleration ($a$), we have that the force with constant mass ($F$) is

$ F = m_i a_0 $

$ F = m_i a $

$F$
Force with constant mass
$N$
9046
$m_i$
Inertial Mass
$kg$
6290
$a$
$a_0$
Constant Acceleration
$m/s^2$
5297

Since the moment ($p$) is defined with the inertial Mass ($m_i$) and the speed ($v$),

$ p = m_i v $



If the inertial Mass ($m_i$) is equal to the initial mass ($m_0$), then we can derive the momentum with respect to time and obtain the force with constant mass ($F$):

$F=\displaystyle\frac{d}{dt}p=m_i\displaystyle\frac{d}{dt}v=m_ia$



Therefore, we conclude that

$ F = m_i a $

ID:(10975, 0)



Medium force

Equation

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The force ($F$) is defined as the momentum variation ($\Delta p$) by the time elapsed ($\Delta t$), which is defined by the relationship:

$ F \equiv\displaystyle\frac{ \Delta p }{ \Delta t }$

$F$
$F$
Force with constant mass
$N$
9046
$\Delta p$
Momentum variation
$kg m/s$
5305
$\Delta t$
Time elapsed
$s$
5103

ID:(3684, 0)



Speed by constant acceleration

Equation

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If the constant Acceleration ($a_0$), then the mean Acceleration ($\bar{a}$) is equal to the value of acceleration, that is,

$ a_0 = \bar{a} $

.

In this case, the speed ($v$) as a function of the time ($t$) can be calculated by considering that it is associated with the difference between the speed ($v$) and the initial Speed ($v_0$), as well as the time ($t$) and the start Time ($t_0$).

$ v = v_0 + a_0 ( t - t_0 )$

$a_0$
Constant Acceleration
$m/s^2$
5297
$v_0$
Initial Speed
$m/s$
5188
$v$
Speed
$m/s$
6029
$t_0$
Start Time
$s$
5265
$t$
Time
$s$
5264

In the case where the constant Acceleration ($a_0$) equals the mean Acceleration ($\bar{a}$), it will be equal to

$ a_0 = \bar{a} $

.

Therefore, considering the speed Diference ($\Delta v$) as

$ \Delta v \equiv v - v_0 $



and the time elapsed ($\Delta t$) as

$ \Delta t \equiv t - t_0 $

,

the equation for the constant Acceleration ($a_0$)

$ a_0 \equiv\displaystyle\frac{ \Delta v }{ \Delta t }$



can be written as

$a_0 = \bar{a} = \displaystyle\frac{\Delta v}{\Delta t} = \displaystyle\frac{v - v_0}{t - t_0}$



and by rearranging, we obtain

$ v = v_0 + a_0 ( t - t_0 )$

.

This equation thus represents a straight line in velocity-time space.

ID:(3156, 0)



Path traveled with constant acceleration

Equation

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In the case of ($$), the speed ($v$) varies linearly with the time ($t$), using the initial Speed ($v_0$) and the start Time ($t_0$):

$ v = v_0 + a_0 ( t - t_0 )$



Thus, the area under this line can be calculated, yielding the distance traveled in a time ($\Delta s$). Combining this with the starting position ($s_0$), we can calculate the position ($s$), resulting in:

$ s = s_0 + v_0 ( t - t_0 )+\displaystyle\frac{1}{2} a_0 ( t - t_0 )^2$

$a_0$
Constant Acceleration
$m/s^2$
5297
$v_0$
Initial Speed
$m/s$
5188
$s$
Position
$m$
9899
$t_0$
Start Time
$s$
5265
$s_0$
Starting position
$m$
5336
$t$
Time
$s$
5264

In the case of the constant Acceleration ($a_0$), the speed ($v$) as a function of the time ($t$) forms a straight line passing through the start Time ($t_0$) and the initial Speed ($v_0$), defined by the equation:

$ v = v_0 + a_0 ( t - t_0 )$



Since the distance traveled in a time ($\Delta s$) represents the area under the velocity-time curve, we can sum the contributions of the rectangle:

$v_0(t-t_0)$



and the triangle:

$\displaystyle\frac{1}{2}a_0(t-t_0)^2$



To obtain the distance traveled in a time ($\Delta s$) with the position ($s$) and the starting position ($s_0$), resulting in:

$ \Delta s \equiv s - s_0 $



Therefore:

$ s = s_0 + v_0 ( t - t_0 )+\displaystyle\frac{1}{2} a_0 ( t - t_0 )^2$

This corresponds to the general form of a parabola.

ID:(3157, 0)



Path with Constant Acceleration as a Function of the Speed

Equation

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In the case of constant acceleration, we can calculate the position ($s$) from the starting position ($s_0$), the initial Speed ($v_0$), the time ($t$), and the start Time ($t_0$) using the equation:

$ s = s_0 + v_0 ( t - t_0 )+\displaystyle\frac{1}{2} a_0 ( t - t_0 )^2$



This allows us to determine the relationship between the distance covered during acceleration/deceleration and the change in velocity:

$ s = s_0 +\displaystyle\frac{ v ^2- v_0 ^2}{2 a_0 }$

$a_0$
Constant Acceleration
$m/s^2$
5297
$v_0$
Initial Speed
$m/s$
5188
$s$
Position
$m$
9899
$v$
Speed
$m/s$
6029
$s_0$
Starting position
$m$
5336

If we solve for the time ($t$) and the start Time ($t_0$) in the equation of the speed ($v$), which depends on the initial Speed ($v_0$) and the constant Acceleration ($a_0$):

$ v = v_0 + a_0 ( t - t_0 )$



we get:

$t - t_0= \displaystyle\frac{v - v_0}{a_0}$



And when we substitute this into the equation of the position ($s$) with the starting position ($s_0$):

$ s = s_0 + v_0 ( t - t_0 )+\displaystyle\frac{1}{2} a_0 ( t - t_0 )^2$



we obtain an expression for the distance traveled as a function of velocity:

$ s = s_0 +\displaystyle\frac{ v ^2- v_0 ^2}{2 a_0 }$

ID:(3158, 0)



Moment (1)

Equation

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The moment ($p$) is calculated from the inertial Mass ($m_i$) and the speed ($v$) using

$ p = m_i v $

$m_i$
Inertial Mass
$kg$
6290
$p$
Moment
$kg m/s$
8974
$v$
Speed
$m/s$
6029

ID:(10283, 1)



Moment (2)

Equation

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The moment ($p$) is calculated from the inertial Mass ($m_i$) and the speed ($v$) using

$ p_0 = m_i v_0 $

$ p = m_i v $

$m_i$
Inertial Mass
$kg$
6290
$p$
$p_0$
Initial moment
$kg m/s$
4974
$v$
$v_0$
Initial Speed
$m/s$
5188

ID:(10283, 2)



Variation of moment with constant mass

Equation

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In the case where the inertial Mass ($m_i$) is constant, the momentum variation ($\Delta p$) is proportional to the speed Diference ($\Delta v$):

$ \Delta p = m_i \Delta v $

$m_i$
Inertial Mass
$kg$
6290
$\Delta p$
Momentum variation
$kg m/s$
5305
$\Delta v$
Speed Diference
$m/s$
5273

As the momentum variation ($\Delta p$) is with the inertial Mass ($m_i$) and the speed Diference ($\Delta v$) equal to

$ p = m_i v $



for the case where mass is constant, the change in momentum can be written with the moment ($p$) and the initial moment ($p_0$), which, combined with the speed ($v$) and the initial Speed ($v_0$), yields

$\Delta p = p - p_0 = m_i v - m_i v_0 = m_i ( v - v_0 ) = m_i \Delta v$



where the speed Diference ($\Delta v$) is computed with:

$ \Delta v \equiv v - v_0 $



thus resulting in

$ \Delta p = m_i \Delta v $

ID:(13998, 0)



Momentum Difference

Equation

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According to Galileo, objects tend to maintain their state of motion, meaning that the momentum

$\vec{p} = m\vec{v}$



should remain constant. If there is any action on the system that affects its motion, it will be associated with a change in momentum. The difference between the initial momentum $\vec{p}_0$ and the final momentum $\vec{p}$ can be expressed as:

$ \Delta p = p - p_0 $

$p_0$
Initial moment
$kg m/s$
4974
$p$
Moment
$kg m/s$
8974
$\Delta p$
Momentum variation
$kg m/s$
5305

ID:(3683, 0)



Mean acceleration

Equation

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The proportion in which the variation of velocity over time is defined as the mean Acceleration ($\bar{a}$). To measure it, it is necessary to observe the speed Diference ($\Delta v$) and the time elapsed ($\Delta t$).

One common method for measuring average acceleration involves using a stroboscopic lamp that illuminates the object at defined intervals. By taking a photograph, one can determine the distance traveled by the object in that time. By calculating two consecutive velocities, one can determine their variation and, with the time elapsed between the photos, the average acceleration.

The equation that describes average acceleration is as follows:

$ a_0 \equiv\displaystyle\frac{ \Delta v }{ \Delta t }$

$ \bar{a} \equiv\displaystyle\frac{ \Delta v }{ \Delta t }$

$\bar{a}$
$a_0$
Constant Acceleration
$m/s^2$
5297
$\Delta v$
Speed Diference
$m/s$
5273
$\Delta t$
Time elapsed
$s$
5103

The definition of the mean Acceleration ($\bar{a}$) is considered as the relationship between the speed Diference ($\Delta v$) and the time elapsed ($\Delta t$). That is,

$ \Delta v \equiv v - v_0 $



and

$ \Delta t \equiv t - t_0 $



The relationship between both is defined as the centrifuge Acceleration ($a_c$)

$ \bar{a} \equiv\displaystyle\frac{ \Delta v }{ \Delta t }$

within this time interval.



It is important to note that average acceleration is an estimation of actual acceleration.

The main problem is that if acceleration varies during the elapsed time, the value of the average acceleration may differ greatly from the mean acceleration

.

Therefore, the key is to

Determine acceleration over a sufficiently short period of time to minimize variation.

ID:(3678, 0)



Speed variation

Equation

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Acceleration corresponds to the change in velocity per unit of time.

Therefore, it is necessary to define the speed Diference ($\Delta v$) in terms of the speed ($v$) and the initial Speed ($v_0$) as follows:

$ \Delta v \equiv v - v_0 $

$v_0$
Initial Speed
$m/s$
5188
$v$
Speed
$m/s$
6029
$\Delta v$
Speed Diference
$m/s$
5273

ID:(4355, 0)



Distance traveled

Equation

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We can calculate the distance traveled in a time ($\Delta s$) from the starting position ($s_0$) and the position ($s$) using the following equation:

$ \Delta s \equiv s - s_0 $

$\Delta s$
Distance traveled in a time
$m$
6025
$s$
Position
$m$
9899
$s_0$
Starting position
$m$
5336

ID:(4352, 0)



Elapsed time

Equation

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To describe the motion of an object, we need to calculate the time elapsed ($\Delta t$). This magnitude is obtained by measuring the start Time ($t_0$) and the the time ($t$) of said motion. The duration is determined by subtracting the initial time from the final time:

$ \Delta t \equiv t - t_0 $

$t_0$
Start Time
$s$
5265
$t$
Time
$s$
5264
$\Delta t$
Time elapsed
$s$
5103

ID:(4353, 0)