Rope tension no friction question

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To determine the tension in the rope needed to accelerate a 1050kg car at 1.20 m/s² horizontally, gravity should not be included in the calculations since the car is not being lifted. The correct approach involves applying Newton's second law only in the horizontal direction, focusing solely on the mass and acceleration. The initial calculations mistakenly included gravitational force, leading to confusion. After clarification and recognizing the error, the correct tension can be calculated without considering gravity. The discussion highlights the importance of correctly applying physics principles in problem-solving.
PearlyD
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Homework Statement


How much tension must a rope withstand if it is used to accelerate a 1050kg car horizontally at 1.20 m/s2? IGNORE FRICTION!



The Attempt at a Solution


What i did was
T-Fg=ma
T-mg=ma
T-1050(9.8)=1050(1.20)
T-10290=1260
T=1.15x10 to the power of 4
But that's not the answer the answer is 1.26x to the power of 3kg
What did i do wrong?
 
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Why are you including gravity? It's not as if you're lifting the car up.

Try drawing a free-body diagram and writing out Newton's second law TWICE, once for the y direction and once for the x direction.
 
ideasrule said:
Why are you including gravity? It's not as if you're lifting the car up.

Try drawing a free-body diagram and writing out Newton's second law TWICE, once for the y direction and once for the x direction.

Sorry i made a dumb mistake!
its been a long day and i was for some reason including gravity in a lot of things that i shouldn't
i got the question now.
thanks for replying anyways:)
 
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