with this tension problem -- Mass on an accelerating cable

AI Thread Summary
To find the tension in the cable supporting a 35 kg mass being raised with a downward acceleration of 1.2 m/s², the equation T = mg + ma is used. The gravitational force (mg) is calculated as 343.35 N, while the force due to acceleration (ma) is 42 N. By substituting these values into the equation, the tension is determined to be approximately 301.35 N. The discussion clarifies that velocity does not influence the tension calculation, as it is not included in the tension formula. The final answer can be rounded for simplicity.
Jett Johnson
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Homework Statement


A 35 kg mass is being raised by a cable with decreasing speed. At the instant the upward velocity has a magnitude of 1.6 m/s and the downward acceleration has magnitude of 1.2 m/s2, what is the tension of the cable?

m=35 kg
v=1.6 m/s
a= -1.2 m/s2
g= 9.81 m/s2

Homework Equations


T=mg+ma

The Attempt at a Solution


My professor may be the worst on the planet and hasn't taught us this, I also cannot find any help in the book or online. I do not know how to input velocity into the tension equation. Please Help Thanks...
 
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Jett Johnson said:
I do not know how to input velocity into the tension equation.
You don't have to. Velocity doesn't affect the tension -- that's why it doesn't appear in the tension equation.
 
So mg= 35 x 9.81 ; ma= 35 x 1.2
T=mg+ma
T= 343.35-42=
301.35 N ?
 
Jett Johnson said:
So mg= 35 x 9.81 ; ma= 35 x 1.2
T=mg+ma
T= 343.35-42=
301.35 N ?
Looks good to me! (You can round off your answer to fewer digits.)
 
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