What caused the cable to break during the lifting of a 4500kg container?

AI Thread Summary
The investigation into the cable break during the lifting of a 4500kg container indicates that the cable's maximum tension capacity is 50,000N. Calculations show that the tension experienced during the lift was 48,645N, which is below the cable's safety rating, suggesting the load was not too heavy. The crane's specifications for speed and acceleration were adhered to, confirming it was not defective. Further analysis indicates that the cable must have been defective, as it failed under conditions that should have been safe. The conclusion is that the cable's integrity was compromised, leading to the accident.
ixbethxi
Messages
13
Reaction score
0
You've been called to investigate an accident in which a cable broke while lifting a 4500kg container. The steel cable is 2.0cm in diameter and has a safety rating of 50,000N. The crane is designed not to exceed speeds of 3.0m/s or accelerations of 1.0m/s^2, and your tests find the crane is NOT defective. what is your conclusion? did the crane operator life too heavy a load or was the cable defective.

can someone check my solution? i don't know if its right

the max tension the cable can hold is 50,000N

T-((4500kg)*(9.81m/s/s))=4500(1.0m/s/s)

T= 48,645<50,000 which means the cable must of been broken because it could possibly hold more.
 
Physics news on Phys.org
What about speed, vertical or horizontal?
 
ixbethxi said:
You've been called to investigate an accident in which a cable broke while lifting a 4500kg container. The steel cable is 2.0cm in diameter and has a safety rating of 50,000N. The crane is designed not to exceed speeds of 3.0m/s or accelerations of 1.0m/s^2, and your tests find the crane is NOT defective. what is your conclusion? did the crane operator life too heavy a load or was the cable defective.

can someone check my solution? i don't know if its right

the max tension the cable can hold is 50,000N

T-((4500kg)*(9.81m/s/s))=4500(1.0m/s/s)

T= 48,645<50,000 which means the cable must of been broken because it could possibly hold more.

Yes. You are somehow right.

If u were to work out the acceleration allowed to lift the weight. 50000-(4500*9.81)= 4500a By working out a, u will get the max acceleration allowed for the lifting of the mass. From there, you can see that the acceleration is more than that of those specified in the qn. Thus, its not that the mass is too heavy but its due to the defective cable.
 
ixbethxi said:
... and your tests find the crane is NOT defective. what is your conclusion?...
 
i concluded that it waas the cable that was defective
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Trying to understand the logic behind adding vectors with an angle between them'
My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...
Back
Top