Invented by Archimedes around 250 BC, a Block is a set of pulleys on an axle in a housing. When rope is run through a block or a series of blocks, the whole assembly is called a Tackle. The most common arrangement is to have one1 block attached to a fixed position and another block left to move with the load being pulled or lifted. The mechanical advantage of a block and tackle is equal to the number of time the same line is attached to or runs through the moving block. The pulley on the left does not have a block on the Bale. When you pull on the rope, you are pulling the full weight of the bail. The tackle on the right has 4 lines running through its pulleys. This would allow you to lift 20 pounds with only about 5 pounds of pressure on the hauling part of the line. While the block and tackle is still used today, it has been largely replaced with the electric winch.
The rope used in the 1800's would have been of natural fiber like we have in this exhibit. The rope around the bail is made of SISAL which comes from the leaves of the agave plant. Cotton rope is running in the blocks. Notice how soft it is compared to the SISAL fiber rope. Jute fiber twine, from the Corchorus plant, is used to tie the ends of the larger ropes. It is the same fiber woven to make burlap sacks. Natural fiber rope continued to be in widespread use until the 1950s when synthetic fibers, such as nylon, became popular.
Answer:
its like a quadrant.
Explanation:q4 ,same thing but negative.
Animals can be classified into two main groups:vertebrates and invertebrates<span>. The main difference between </span>vertebrates and invertebrates<span> is that</span>invertebrates<span>, like insects and flatworms, </span>do<span> not</span>have<span> a backbone or a spinal column. Examples of</span>vertebrates<span> include humans, birds, and snakes. hope this helped</span>
Answer:
The correct answer is - C. euglena and volvoxes
Explanation:
All the given options are the organism from the protist. Protist is the group of organism shows various type of organism including the autotrophs and heterotrophs. Amoeba is an organism that is a consumer as it engulfs food particles.
Paramecium is also a consumer as it does not produce its own food whereas volvoxes and euglenas are the photosynthesis organism that is capable of producing their own food.
