Acceleration of a particle

Tucta

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A particle is moving on a straight line path with acceleration given by:

. . . . .\(\displaystyle \dfrac{dv}{dt}\, =\, -2\, e^{-x}\)

where x is the distance of the particle from the origin and v is the velocity of the particle.

Knowing that:

. . . . .\(\displaystyle \dfrac{d}{dx}\, \left(\dfrac{v^2}{2}\right)\, =\, \dfrac{dv}{dt}\)

hence determine that if v = 2 when x = 0 then:

. . . . .\(\displaystyle v\, =\, 2\, e^{-x/2}\)



I'm at a complete loss, don't understand what the question is asking me to do.
 

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A particle is moving on a straight line path with acceleration given by:

. . . . .\(\displaystyle \dfrac{dv}{dt}\, =\, -2\, e^{-x}\)

where x is the distance of the particle from the origin and v is the velocity of the particle.

Knowing that:

. . . . .\(\displaystyle \dfrac{d}{dx}\, \left(\dfrac{v^2}{2}\right)\, =\, \dfrac{dv}{dt}\)

hence determine that if v = 2 when x = 0 then:

. . . . .\(\displaystyle v\, =\, 2\, e^{-x/2}\)



I'm at a complete loss, don't understand what the question is asking me to do.
You are being asked to show that the velocity "v" can be expressed in a certain way.

You have been given two different expressions for dv/dt. What you learned back in algebra suggests an equation you can make with this. Where does this equation lead? ;)
 
Last edited:
A particle is moving on a straight line path with acceleration given by:

. . . . .\(\displaystyle \dfrac{dv}{dt}\, =\, -2\, e^{-x}\)

where x is the distance of the particle from the origin and v is the velocity of the particle.

Knowing that:

. . . . .\(\displaystyle \dfrac{d}{dx}\, \left(\dfrac{v^2}{2}\right)\, =\, \dfrac{dv}{dt}\)

hence determine that if v = 2 when x = 0 then:

. . . . .\(\displaystyle v\, =\, 2\, e^{-x/2}\)



I'm at a complete loss, don't understand what the question is asking me to do.
.

\(\displaystyle \frac{d}{dx}\left[\frac{v^2}{2}\right] \ = -2*e^{-x}\)

\(\displaystyle d\left[\frac{v^2}{2}\right ] \ = -2*e^{-x} \ dx\)

Now integrate both sides - and you are done.....
 
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A particle is moving on a straight line path with acceleration given by:

. . . . .\(\displaystyle \dfrac{dv}{dt}\, =\, -2\, e^{-x}\)

where x is the distance of the particle from the origin and v is the velocity of the particle.

Knowing that:

. . . . .\(\displaystyle \dfrac{d}{dx}\, \left(\dfrac{v^2}{2}\right)\, =\, \dfrac{dv}{dt}\)

hence determine that if v = 2 when x = 0 then:

. . . . .\(\displaystyle v\, =\, 2\, e^{-x/2}\)



I'm at a complete loss, don't understand what the question is asking me to do.
I realized that dv/dt = d(2e^-x +c)/dx
 
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