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Question:

Need help finding the tension on the string.?

Here's the problem:A crane lifts the 18,000 kg steel hull of a ship out of the waterDetermine (a) the tension in the crane's cable when the hull is submerged in the water and (b) the tension when the hull is completely out of the waterAll I can think of is the mass of the hull and the acceleration (gravity) and the density of the water.What I am asking for:How would i find the tension of the string? What equation should I useAlso, when the hull is in the water how would I include the density of the water into an equation that finds the tension of the cranes cable? Also the rest of the questions to the problemThank you.

Answer:

when the ship is out of the water the tension is the weight of the ship (18,000kg x 9.8m/s/s) when the ship is in the water, the tension will be the weight minus the buoyant force of the water; the buoyant force of the water is the weight of the water displaced by the ship, which is density of water x g x volume displaced they need to give you some information about the volume of the ship, if they don't, look up the density of steel and use that with the mass to estimate a volume, but hull's are not usually solid steel, so this technique will have some error.but if they don't give you information to find the volume of the hull, that is what you will have to do (density of steel is something like 7800kg/m^3, so the volume is a bit over 2 m^3; the tension in the cable is tension when ship is submerged weight of ship in air - buoyant force of water
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New carpet and blanketsThe bad part is that cats and dogs will always be able to smell it and it will upset some of them and they will wanna mark over it.
One thing that works really well is a product I got in a pet store called Urine GoneIt has enzymes in it that break down the stain and help leave it smelling good.
You can get pet odor sprays from Wal-Mart for about $3.50They work miracles: just spray it everywhereI had a cat that got locked in the house for three daysThere was plenty of food and water for him, just no litter boxNaturally, when I got home, he had gone all over the place and the apartment reeked to high heavenAfter cleaning up the piles, I took a bottle of pet odor spray and just went to town all over my apartmentWithin an hour, I had company over, and no one could tell that anything was amissIt just worked wondersEven delicate noses will be placated by pet odor sprays.
Blankets or anything that can go into the washing machine, should be washed with hot waterThis will take care of any odorsAs far as the carpet, Natures Miracle and other products like it really do work.

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