when building a house, wich of the following is a simple machine that
a construction worker would use?
A)plywood
B)safety hat
C)cement
D)pulley
Plywood is a material.
A safety hat is an object.
Cement is a material.
A pulley is a simple machine.
For simple minded people who sit there and don't do the work here are the answers to start of the unit here are some notes
ANSWERS HERE YOU LITERALLY DIVIDE INTO A CALCULATOR. It took me about 15 min
1) A
2) C
3) A
4) D
Friction is a force that opposes motion and wastes both energy and work in the process. In machines, moveable parts rub against each other. In order to get the parts moving and keep them moving, you must overcome friction. Part of your work input is used to overcome the friction that keeps things stationary. Once things are in motion, friction works against that motion. It not only slows things down, but it also generates heat and causes parts to wear out. Reducing friction in a machine can make the machine more efficient and require less energy input to perform a given task. The less friction there is among the moving parts of a machine, the more efficient it is at converting work input into work output. You can calculate efficiency with the following equation:
EFFICIENCY=WORK OUTPUT OVER WORK INPUT X 100%
very often, plywood is used for a ram to move heavy material over ridges. Pulley is probably intended here, but plywood ramps are very handy and useful.
A construction worker on a high-rise building is on a platform suspended between two cables as illustrated below. The construction worker weighs 850 N, the plank weighs 450 N, and the tension in the left cable is 550 N
If you are here after the test I want to say good job...
getting a 3/5 :)
a pulley
The simple machine that a construction worker would use from the options given is a pulley. To determine this, we need to understand what the different options are and how they are used in construction.
A) Plywood: While plywood is an essential material for constructing walls, floors, and roofs, it is not a simple machine. It falls under the category of building materials.
B) Safety hat: A safety hat, also known as a hard hat, is an essential safety equipment for construction workers. However, it is not considered a simple machine.
C) Cement: Cement is a vital material used in construction to make concrete for foundations, walls, and other structures. Like plywood, it is not a simple machine but belongs to the category of building materials.
D) Pulley: A pulley, on the other hand, is a simple machine used to lift heavy loads with less effort. It consists of a grooved wheel and a rope or cable that runs through the groove. By pulling one end of the rope, the construction worker can lift or move heavy objects, such as building materials or equipment, with reduced effort.
Therefore, the correct answer is D) pulley.