my house is older.it has a crawlspaceI want to put insulation in it but I don't have a clue how much it could cost? Anyone have a clue? I live in texas if that means anything.
I don't understand why only the mass but not the radius of the pulley is givenI think you need the pulley's moment of inertia in order to find the tension in the cable between the pulley and drumHere's how I'd tackle this problem: First, find the tension in the cable lifting the crate as done by othersThen find the angular acceleration of the pulley and use its moment of inertia to find the torque required to spin it up as the crate accelerates upwardUse that the find the difference in the tensions in the cables on both sides of the pulleyThat will give the tension in the cable coming off the drumThe torque the engine applies to the drum will have to spin up the drum (you are given enough info to find its moment of inertia) and provide the required tension in the cableUnless the radius of the pulley cancels out somehow (I don't see how) I don't see how there's enough info to solve this fullyDid you leave out a piece of information? The fact that it's described as solid cylindrical sounds like a cue to finding its moment of inertia that has me puzzledI'll come back with more if a solution hits me later.
The 180 kg crate is accelerating upward at a rate of 1.2 m/s?, which also overcomes gravity (9.8 m/s?)That's 11.0 m/s?, if you add them togetherThat's a weight of 180 kg 11.0 m/s? 1980 N Similarly, the pulley weight is 130 kg 9.8 m/s? 1274 N(It's not accelerating up or down, like the crate is.) Add these together, and you get the total tension force on the cable The torque is then given by T F R, where R is the radius of the drumYou don't yet need the mass of the drum, but you might need it later, to calculate its moment of inertia.
Unless you live above a natural geothermal location, there really isn't any reason to attach insulation to the topside of your crawlspaceIn fact, it may cause curious critters to try and gain access to what may be perceive as a viable food source Better you should check the insulation in your roof/ceiling/atticSince heat does rise, if the insulation is poor, perhaps the heat is escaping into an atticAlso, check insulation around windows and door, close chmney flues, etcGood luck
