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

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SUMMARY

The acceleration function derived from the velocity equation v=√(2P/M)(√T) is a=√(P/2MT). The discussion highlights the importance of treating constants correctly when differentiating with respect to time. Participants clarified that P (power in watts) and M (mass) are constants, while T represents time. The correct differentiation process leads to the desired acceleration function, confirming that understanding the roles of each variable is crucial in deriving the correct answer.

PREREQUISITES
  • Understanding of calculus, specifically differentiation techniques.
  • Familiarity with the concepts of velocity and acceleration in physics.
  • Knowledge of how to manipulate algebraic expressions involving square roots.
  • Basic understanding of physical quantities such as power, mass, and time.
NEXT STEPS
  • Study the principles of differentiation in calculus, focusing on the chain rule and product rule.
  • Learn about the relationship between velocity and acceleration in kinematics.
  • Explore the implications of treating constants versus variables in differentiation.
  • Practice deriving functions from physical equations in various contexts, such as mechanics.
USEFUL FOR

Students studying physics and calculus, particularly those focusing on kinematics and differentiation techniques. This discussion is also beneficial for anyone looking to improve their problem-solving skills in deriving functions from equations.

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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