probably to drive the motor, I dont really know sorry
Pulleys are commonly used in devices that move things up and down. Steam-shovels, scaffolding for construction or painting, elevators for freight or passengers, devices for lowering boats into the water are likely to contain pulleys. Pulleys and belts are used to transfer power-- cars and buses usually have a fan belt with pulleys.
For internal pulleys located in the engine compartment which are used for the fan belts, the radiator has to be removed. If the radiator's not removed, it will be too cramped to work. Un bolting the pulley supports allow the pulleys to retract an 1/8 to 1/4 inch or so allowing the belts to come off, or cut them, then stretch the new ones on. Outside towing pulleys are simple bolt on jobs; ALWAYs attached to the chasis frame of course!
"B" series v-belts are wider and transmit more horsepower than "A" series belts. V-belt sheaves for A and B series belts often will accept both A or B series belts. These sheaves will usually have pitch diameters stamped on them for both A and B. You will notice the diameter for the "A" belt will be a little smaller pitch diameter because the "A" belt will ride "down" in the groove farther than the "B" belt. You should be able to "google" on something like "gates v-belts" to see examples. DNC
Yes, record players use electricity. The first ones used a spring, you wind up the little handle on the side and let it play.
V Belt is thin and V in shape, and is normally used to power a single component in a system of pulleys. Serpentine Belt is wider, and is used to drive multiple components in automotive engine, it loops continuous over several pulleys. In addition, V Belts are normally found in older automotives.
There are "v" belts, "serpentine" belts and "timing" belts.
pulleys
pickering governor
Because they must be flexible and often operate under extreme temperatures they are often made of rubber or plastic. Because of the friction between the belt and pulleys they get hot and stretch.
assuming that your question is what jobs are pulleys used for... then the answer is any job that you need to lift something that is heavy. The pulley give a mechanical advantage when used together with other pulleys to apply more force to move the object
Squeaking belts are the result of improperly adjusted tensioners and pulleys. The belt slides over the pulley and squeaks. Using a lubricant would defeat the purpose. Also I'm not sure what affect wd-40 would have on the material the belts are made of. To get them to stop squeaking tighten them up. Make sure you use your manual and don't get them too tight.
Different types of belts have many different uses depending on the need. Drive belts are used for an engines's fly wheel. Weightlifting belts are used to support a person when lifting weights. Seat belts are used to protect drivers and passengers in automobiles.