Translational kinetic energy

Storyboard

The kinetic energy of translation is a function of the velocity achieved through the application of a force over a given time while traveling a given path.Thus, the kinetic energy of translation is proportional to the mass of the object and the square of the velocity.

>Model

ID:(753, 0)



Translational kinetic energy

Model

The kinetic energy of translation is a function of the velocity achieved through the application of a force over a given time while traveling a given path. Thus, the kinetic energy of translation is proportional to the mass of the object and the square of the velocity.

Variables

Symbol
Text
Variable
Value
Units
Calculate
MKS Value
MKS Units
$\Delta s$
Ds
Distance traveled in a time
m
$F$
F
Force with constant mass
N
$m_i$
m_i
Inertial Mass
kg
$v_0$
v_0
Initial Speed
m/s
$W_0$
W_0
Initial work
J
$a$
a
Instant acceleration
m/s^2
$s$
s
Position
m
$v$
v
Speed
m/s
$\Delta v$
Dv
Speed Diference
m/s
$t_0$
t_0
Start Time
s
$s_0$
s_0
Starting position
m
$t$
t
Time
s
$\Delta t$
Dt
Time elapsed
s
$W$
W
Work
J
$\Delta W$
DW
Work variance
J

Calculations


First, select the equation:   to ,  then, select the variable:   to 

Symbol
Equation
Solved
Translated

Calculations

Symbol
Equation
Solved
Translated

 Variable   Given   Calculate   Target :   Equation   To be used



Equations

The energy required for an object to change its angular velocity from $\omega_1$ to $\omega_2$ can be calculated using the definition

$ \Delta W = T \Delta\theta $



Applying Newton's second law, this expression can be rewritten as

$\Delta W=I \alpha \Delta\theta=I\displaystyle\frac{\Delta\omega}{\Delta t}\Delta\theta$



Using the definition of angular velocity

$ \bar{\omega} \equiv\displaystyle\frac{ \Delta\theta }{ \Delta t }$



we get

$\Delta W=I\displaystyle\frac{\Delta\omega}{\Delta t}\Delta\theta=I \omega \Delta\omega$



The difference in angular velocities is

$\Delta\omega=\omega_2-\omega_1$



On the other hand, angular velocity itself can be approximated with the average angular velocity

$\omega=\displaystyle\frac{\omega_1+\omega_2}{2}$



Using both expressions, we obtain the equation

$\Delta W=I \omega \Delta \omega=I(\omega_2-\omega_1)\displaystyle\frac{(\omega_1+\omega_2)}{2}=\displaystyle\frac{I}{2}(\omega_2^2-\omega_1^2)$



Thus, the change in energy is given by

$\Delta W=\displaystyle\frac{I}{2}\omega_2^2-\displaystyle\frac{I}{2}\omega_1^2$



This allows us to define kinetic energy as

$ K_t =\displaystyle\frac{1}{2} m_i v ^2$

(ID 3244)

The energy required for an object to change its angular velocity from $\omega_1$ to $\omega_2$ can be calculated using the definition

$ \Delta W = T \Delta\theta $



Applying Newton's second law, this expression can be rewritten as

$\Delta W=I \alpha \Delta\theta=I\displaystyle\frac{\Delta\omega}{\Delta t}\Delta\theta$



Using the definition of angular velocity

$ \bar{\omega} \equiv\displaystyle\frac{ \Delta\theta }{ \Delta t }$



we get

$\Delta W=I\displaystyle\frac{\Delta\omega}{\Delta t}\Delta\theta=I \omega \Delta\omega$



The difference in angular velocities is

$\Delta\omega=\omega_2-\omega_1$



On the other hand, angular velocity itself can be approximated with the average angular velocity

$\omega=\displaystyle\frac{\omega_1+\omega_2}{2}$



Using both expressions, we obtain the equation

$\Delta W=I \omega \Delta \omega=I(\omega_2-\omega_1)\displaystyle\frac{(\omega_1+\omega_2)}{2}=\displaystyle\frac{I}{2}(\omega_2^2-\omega_1^2)$



Thus, the change in energy is given by

$\Delta W=\displaystyle\frac{I}{2}\omega_2^2-\displaystyle\frac{I}{2}\omega_1^2$



This allows us to define kinetic energy as

$ K_t =\displaystyle\frac{1}{2} m_i v ^2$

(ID 3244)

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,

$ dv \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.

(ID 3678)

If we start from the starting position ($s_0$) and want to calculate the distance traveled in a time ($\Delta s$), we need to define a value for the position ($s$).

In a one-dimensional system, the distance traveled in a time ($\Delta s$) is simply obtained by subtracting the starting position ($s_0$) from the position ($s$), resulting in:

$ \Delta s = s - s_0 $

(ID 4352)

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)


Examples


(ID 15526)


(ID 15471)


ID:(753, 0)