Calculating Safety of Lifting Steel Beam at 3m/s

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To determine if it is safe to lift a 350 kg steel beam at a constant speed of 3 m/s, it is crucial to recognize that constant speed implies zero acceleration. This means the net force acting on the beam is also zero, indicating that the tension in the supporting cable must equal the weight of the beam. The weight of the beam can be calculated using the formula F = ma, resulting in a force of approximately 3,430 Newtons (350 kg x 9.81 m/s²). Since this tension is significantly less than the cable's maximum capacity of 7,000 Newtons, it is safe to lift the beam at that speed. Therefore, lifting the beam at a constant speed of 3 m/s is indeed safe.
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i have this question

a crane is raising a steel beam (350 kg) the max tension the supporting cable can take without breaking is 7000 Newtons

a) is it safe to life the beam at a constant speed of 3m/s? prove answer

(the only idea i have is the use of f=ma, but then i am stuck w/acceleration when i need to use speed i just don't know what to do.)
:confused: :confused: :confused:
 
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if something is traveling at a constant speed, what is its acceleration? What does this mean about your NET force?
 
As a physics student, I cannot be completely sure of answering this as some of experts in this forum would, but I'll do it anyway..

Don't be too mindful of the "3m/s" as a quantity.
however, be mindful that it's moving at a constant speed.
That means there is NO acceleration.

As Dave said, what does that make your Net force?

Draw a free body diagram to see what forces are acting on the steel beam.
Then see if the tension on the cable is greater than 7,000 Newtons.
 
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