Problem related to Newton's Laws

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The discussion revolves around solving a physics problem related to Newton's Laws, specifically addressing the motion of two objects with different weights and no friction. The user attempts to calculate the acceleration and tension in the system, using the equations of motion for both masses. They correctly derive the acceleration as 2.94 m/s² and the tension as 35.3 N, confirming their calculations align with the principles of equilibrium and forces. The importance of mass in determining motion is highlighted, particularly in how it influences tension and acceleration. The steps taken in the calculations are validated, affirming their correctness.
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Homework Statement


34t2ycw.jpg



Homework Equations


ƩF=0
ƩF= m a


The Attempt at a Solution


Since there is no friction do I assume the objects will move?
or it will remain equilibrium since m1 is 120N which is way higher than 50N.
 
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RuthlessTB said:
Since there is no friction do I assume the objects will move?
or it will remain equilibrium since m1 is 120N which is way higher than 50N.
Why would the weight of m1 matter? (The mass of m1 matters though.)

Note that m1 moves horizontally while m2 moves vertically.
 
m1:
T - 0 = m1 a

m2:
m2g - T = m2 a

I need now to calculate acceleration first in order to get the value of the tension

T = m1 a
-T + m2g = m2 a

[m2g = a(m1+m2)]
50 = a(12+5)
a= 50/17 = 2.94 m/s^2

Now to calculate the tension
T= m1 a
T= 12 (2.94) = 35.3 N

My question is, are the steps in red color right?
 
RuthlessTB said:
m1:
T - 0 = m1 a

m2:
m2g - T = m2 a

I need now to calculate acceleration first in order to get the value of the tension

T = m1 a
-T + m2g = m2 a

[m2g = a(m1+m2)]
50 = a(12+5)
a= 50/17 = 2.94 m/s^2

Now to calculate the tension
T= m1 a
T= 12 (2.94) = 35.3 N

My question is, are the steps in red color right?
Yes, using a value of g = 10 m/s^2.
 
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