Acceleration of a Bucket and Tension Forces

AI Thread Summary
The discussion centers on calculating the acceleration of a 14.0 kg bucket being lowered by a rope with a tension of 169 N. The initial calculation incorrectly suggested the acceleration was downward, but it was clarified that the net force is upward since the tension exceeds the weight of the bucket. Using Newton's second law, the correct approach involves analyzing the forces acting on the bucket. The conclusion is that the bucket's acceleration is upward due to the greater tension force compared to its weight. The final acceleration value is determined to be positive, indicating upward motion.
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Homework Statement



A 14.0 bucket is lowered vertically by a rope in which there is 169 of tension at a given instant.

What is the acceleration of the bucket?

Is it up or down?

Homework Equations



F = ma

The Attempt at a Solution



F / m = a

(169 N) / (14 kg ) = 9.81 m/s^2 - x

12.07 m / s ^2 - 9.81 m/s^2 = - x

2.3 m/s^2 = - x
-2.3 m/s^2 = x

I initially thought the acceleration of the bucket was down because of what I got for "x" but that is incorrect. Is the acceleration of the bucket up because 9.81 - (-2.3 ) = +12.07 ?
 
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You are correct that the acceleration is up. But you shouldn't be solving the problem by your method. Instead, draw a free body diagram and use Newton's 2nd law, which states that F_{net} = ma, where F_{net} is the sum of the tension force up and the weight force mg down. Since the Tension force is greater than the weight, the net force, and acceleration, must be up.
a = __?___?
 
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