Combine the expressions for tension and solve for acceleration

AI Thread Summary
The discussion focuses on deriving an equation for the acceleration of a cart and suspended mass, incorporating both masses, the incline angle, and gravitational acceleration. Participants are attempting to combine tension equations to solve for acceleration but are encountering difficulties with notation and algebraic manipulation. The correct approach involves eliminating one unknown variable to simplify the equations. Clarification is suggested regarding the use of consistent mass notation to avoid confusion. The thread emphasizes the importance of clear algebraic steps in reaching the final derived equation.
asusal
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1. Derive an equation for the acceleration of both the cart and suspended mass in
terms of both masses (Mc and Ms ), the angle of the incline (θ), and the acceleration due to gravity (g).


Homework Equations


Fx=
T - Mgsin θ = Ma

T = Mgsin θ + Ma
Fy
T = mg - ma

Combine the expressions for Tension and solve for the acceleration.

A= (mg - Mg sin θ / M + m )

https://imgur.com/a/Okk79t9 (I know in the picture it's already derived in the correct form I just want to know how they got that correctly.)[/B]

The Attempt at a Solution



So I combined the equations

T= (ms*g-mc*g*sin(θ) ) / ( mc + mg)

T= ms (g- (ms*g-mc*g*sin θ/ mc+ms) )

[/B]
I'm assuming I factor MS and common denom but it doesn't seem like I'm doing this correctly.
Any help would be appreciated!

Thanks.
 
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asusal said:
So I combined the equations
T= (ms*g-mc*g*sin(θ) ) / ( mc + mg)
T= ms (g- (ms*g-mc*g*sin θ/ mc+ms) )

I'm assuming I factor MS and common denom but it doesn't seem like I'm doing this correctly.
Any help would be appreciated!

Can you show more of your working?

Why introduce ms and mc ? In the image they use "M" for the mass of the cart and "m" for the suspended mass. I suggest you stick to that notation.
 
Hint: When you combine two equations you can frequently eliminate one unknown variable. Which unknown doesn't appear in the final equation given to you?
 
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