Equal to the number of cords supporting the weight.
Block and tackle refers to a rope threaded through a series of pulleys to provide mechanical advantage, and it is used to lift heavy objects,
Of a single pulley wheel, only that it changes the direction of the force ie: from overhead. > On a block and tackle system, 2 or more pulley wheels are used in a certain way to produce mechanical advantage. The simplest type of block and tackle offers a mechanical advantage of 2
cranes have block and tackle pulleys.
A block and tackle is a series of pullys lifting heavy whates
mechanical advantage
Block and tackle refers to a rope threaded through a series of pulleys to provide mechanical advantage, and it is used to lift heavy objects,
Of a single pulley wheel, only that it changes the direction of the force ie: from overhead. > On a block and tackle system, 2 or more pulley wheels are used in a certain way to produce mechanical advantage. The simplest type of block and tackle offers a mechanical advantage of 2
look in your ducking textbook
The mechanical advantage is that the force applied increases but that is compensated by the fact that the rope or chain needs to be moved through a greater distance.
The block and tackle is still used in the manner it has always been used, to gain a mechanical advantage in lifting or pulling objects. It is used extensively aboard ships today. I used them in the Navy. I have also used the block and tackle on construction jobs when rigging heavy loads to move them. The block and tackle is very handy when there is no source of electric power available and in remote locations.
By mechanical advantage. The multiple lengths of rope divide the force needed to lift an object everytime the rope reverses direction thru a pully.
A single pulley simply changes the direction of the force. A block and tackle or multiple pulleys can offer a mechanical advantage - same as an inclined plane. For the same mechanical advantage, a pulley system may be better because of lower friction.
The ideal mechanical advantage is calculated as: Ideal_Mechanical_Advantage = distance_moved_by_effort / distance_moved_by_load. It is ideal because it ignores real world factors like energy lost through friction. So an Ideal Mechanical Advantage (IMA) of 7 means that the machinery amplifies the applied effort by 7. For example, a 7 kg load can be balanced using a block-and-tackle arrangement (which has 7 ropes supporting the load block and thus an IMA of 7) using only 1 kg and lifted by applying slightly more than 1 kg. In the real world, there is friction between the pulleys and their bearings so that more real effort is required before the load moves and the real Mechanical Advantage of the above block-and-tackle arrangement is less than 7.
Hi Gretchen, this arrangement to gain mechanical advantage is often referred to as a "block and tackle". It consists of pulleys and ropes, usually not more than four, where the pulley attached to the load moves with the load, and the mechanical advantage is determined by the number of ropes.
The answer depends on the quality of the components used. It also depends on whether you use a simple system with just 2 blocks, or use a cascaded system where the output of one block and tackle feeds the input to another. The only other answer I can give is "it's fewer than you think".
In theory there is no difference in efficiency (it would be 1), but in practice I think a block and tackle would lose more force to friction in the pulleys and between the rope and pulleys.
A block and tackle consists of a system of pulleys with a rope and hook. It is a simple machine which lets you lift a heavy weight more easily. We say it gives you a mechanical advantage,or that it is a force multiplier because it lets you trade a large distance by which you pull the rope using a small effort for a small distance lifting the heavy weight. An example is an engine hoist.