How Do You Derive the Acceleration Function from a Given Velocity Equation?

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Homework Help Overview

The discussion revolves around deriving the acceleration function from a given velocity equation, specifically v=√(2P/M)(√T). Participants are exploring the relationship between power, mass, and time in the context of this derivation.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the process of differentiation and the roles of the variables P, M, and T. There is a focus on understanding how to treat these variables during differentiation, particularly whether they are constants or functions of time.

Discussion Status

Some participants have provided clarifications regarding the definitions of the variables and the nature of acceleration as the derivative of velocity with respect to time. There is acknowledgment of a misunderstanding regarding the treatment of constants in the differentiation process.

Contextual Notes

There is a mention of a specific context involving the velocity of a car, where P represents power in watts, M is mass, and T is time. This context may influence how participants approach the problem and their assumptions about the variables involved.

david98999
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Homework Statement



Derive the function for the acceleration from this function

v=√(2P/M)(√T)

The answer is √(P/2MT)

I have tried many different attempts but I am still unable to reach this answer.
[/B]
I am sure the process to get to the answer is a simple one but for some reason I am unable to see it

Homework Equations


I use the normal method of deriving the function , for each variable i use anx^(n-1)

The Attempt at a Solution



We have 3 variables P , M and T

derivative of P

(1/2)P^(-1/2) =1/(2√P)

derivative of M

(-1/2)M^(-3/2)= -M^(-3/2)/2

Derivative of T

(1/2)T^(-1/2)= 1/(2√T)these answers do not make up the final sum as m is negative ,

I just need to understand the process to get to the answer for this particular sum , not the subject in generalI can derive and integrate functions (ex: 3x^2= 3(2)x^(2-1)=6x and 6x^2/2=3x^2)
its just that I do not understand how to derive this equation into the given answer ,
I have a mental block about this question.I would appreciate any help

 
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david98999 said:

Homework Statement



Derive the function for the acceleration from this function

v=√(2P/M)(√T)

The answer is √(P/2MT)

I have tried many different attempts but I am still unable to reach this answer.
[/B]
I am sure the process to get to the answer is a simple one but for some reason I am unable to see it

Homework Equations


I use the normal method of deriving the function , for each variable i use anx^(n-1)

The Attempt at a Solution



We have 3 variables P , M and T

derivative of P

(1/2)P^(-1/2) =1/(2√P)

derivative of M

(-1/2)M^(-3/2)= -M^(-3/2)/2

Derivative of T

(1/2)T^(-1/2)= 1/(2√T)these answers do not make up the final sum as m is negative ,

I just need to understand the process to get to the answer for this particular sum , not the subject in generalI can derive and integrate functions (ex: 3x^2= 3(2)x^(2-1)=6x and 6x^2/2=3x^2)
its just that I do not understand how to derive this equation into the given answer ,
I have a mental block about this question.I would appreciate any help

It's not clear what P and M stand for in the formula for velocity. Is T supposed to represent time?

The acceleration has a very specific definition: it is the derivative of the velocity with respect to time. If P or M are not functions of time, then they are treated as constants when taking any derivatives w.r.t. time.
 
SteamKing said:
It's not clear what P and M stand for in the formula for velocity. Is T supposed to represent time?

The acceleration has a very specific definition: it is the derivative of the velocity with respect to time. If P or M are not functions of time, then they are treated as constants when taking any derivatives w.r.t. time.

sorry the function is to find the velocity of an alfa romero car , p= the power in watts , m is the mass and t is the time , the question wants me to derive the velocity as a function of time
 
david98999 said:
the question wants me to derive the velocity as a function of time

So M and P are constants ... You should only differentiate with respect to time.
 
You are right I did as you said

√(2p/m)*√t

a=dv/dt=(2p/m)^(1/2) x t^1/2 = 2^(-1) x (2p/m) ^(1/2) x t^(-1/2)
= √(2p/(m(2)^2)t)= √(p/2mt)

I had a feeling it was a simple error , I'm sorry I wasted every ones' time.
Thank you for your help
 

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