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Which pieces of equipment are used for obtaining solids for measuring mass

Measuring specific amounts of liquids (65 mL) Spatula Measuring/removing small amounts of solids or powders (often when obtaining mass) Wash bottle Used to wash down specific pieces of equipment with water or keep materials moist. Micropipets Used to measure and dispence very small amounts of liquids. (ex. 0.5 mL Mass Measuring Equipment. Analytical Balance. The analytical balance is the common piece of equipment in the scientific laboratory. These highly precise instruments can measure down to ten thousandths or even hundred thousandths of a gram. M odern analytical balances use a complex system of electronic sensors to accurately mass a substance Which pieces of equipment are used for heating other substances? Bunsen Burner Hot Plate Laboratory Incubator Laboratory Oven 4. Which pieces of equipment are used for obtaining solids for measuring mass? Triple-beam Balance Spatul In science, a mass spectrometer is a piece of equipment used to measure the weight of charged particles. This is done by combining both electric and magnetic fields to make those measurements

  1. Equipment for Measuring Mass To find the mass of an object, a scale balance is used. The most common types of scale balances are the triple beam balance (figure 1-12) and the electronic balance (figure 1-13). Both types of balances measure mass in grams. Spring Scale Weight or force is measured using a spring scale. Your bathroom scale is
  2. e the mass of this flask. Use the electronic balance in the weigh room to deter
  3. A beaker is a common container in most labs. It is used for mixing, stirring, and heating chemicals. Most beakers have spouts on their rims to aid in pouring. They also commonly have lips around their rims and markings to measure the volume they contain, although they are not a precise way to measure liquids. Beakers come in a wide range of sizes
  4. Equipment used to handle material at a single location (e.g., to feed and/or manipulate materials so that are in the correct position for subsequent handling, machining, transport, or storage). Unlike transport equipment, positioning equipment is usually used for handling at a single workplace. Material can also be positioned manuall
  5. Pressure Gauge. Pressure gauges are a really common and crucial measuring tool. These types of gauges are used in many different things, and you will find that owning one will come in handy. The measurement tool being shown here is a water pressure gauge

While a slotted spoon is primarily used to retrieve solid ingredients from a cooking pot that may also preserve liquid, it can be used as a measuring kitchen utensil as well. How, you may wonder Scoopula - A scoopula is a metal spatula-type utensil used to scoop up solids such as powders in a chemistry lab. Stirring rod - A skinny solid glass rod used in chemistry to mix chemicals and liquids. A stirring rod is typically about the length of a long straw and has rounded ends Graduated in mL. Beaker. (glass or plastic) Used to stir, heat (if glass), and measure liquid volume in mL (rough estimate). Beaker Tongs. Used to handle hot beakers. Florence Flask. Glassware used to heat and store substances. Erlenmeyer Flask

Mass - Laboratory Equipmen

  1. Buoyant weight (solids) Overflow trough (solids) Measuring cup (grained solids, liquids) Flow measurement devices (liquids) Graduated cylinder (liquids) Pipette (liquids) Eudiometer, pneumatic trough (gases) If the mass density of a solid is known, weighing allows to calculate the volume. For the ranges of volume-values see: Orders of magnitude (volume
  2. Erlenmeyer flasks are used to measure, mix, and store liquids. The shape makes this flask very stable. They are one of the most common and useful pieces of chemistry lab glassware. Most Erlenmeyer flasks are made of borosilicate glass so that they can be heated over a flame or autoclaved
  3. Laboratory glassware: These are laboratory materials for measuring, pipetting, transferring, preparation of reagents and storage. They include beakers, bottles, condensers/distillation, flasks, funnels, glass washers/dryers, test tubes, and vials. Clinical lab equipment: These are apparatus mostly used in clinical areas, mostly in hospitals. They include blood/gas analyzers, cell counters, chemistry analyzers, coagulation analyzers, and haematology analyzers
  4. Thickeners are used to separate solids from liquids by means of gravity sedimentation. Most thickeners are larger, continuous operation pieces of equipment. They are used for heavy duty applications such as coal, iron ore taconites, copper pyrite, phosphates, and other beneficiation processes
  5. The plastic pieces protect the ears from the metal. The twisting helps to improve the quality of sound heard through the stethoscope. The stethoscope should be worn with the earpieces forward (figure 5-4) to help prevent the sounds picked up by the diaphragm from being distorted. Figure 5-4. Earpiece of stethoscope in place for use
Section 2 - Laboratory Equipment and Functions

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What piece of science equipment is used for measuring mass

including routine maintenance plans for each piece of equipment. The plan should specify the frequency with which all maintenance tasks should be performed. • Develop the format for records, create logs and forms, and establish the processes to maintain records. • Train staff on the use and maintenance of the equipment, and assure that al The equipment in food processing refers to processing machines, components, systems used to cook, handle, package, prepare or store food and food products. Although this equipment is primarily aimed towards consumability, preservation, palatability, few pieces of equipment also perform auxiliary or main functions such as preparation, handling.

1: Measurements in the Laboratory (Experiment) - Chemistry

The devise that is used for measurement of certain physical quantity is called as measuring instrument. There are two main types of the measuring instruments: analogue and digital. The analogue instruments indicate the magnitude of the quantity in the form of the pointer movement. The digital measuring instruments indicate the values of the quantity in digital format that is in numbers, which. 5. Put on all safety equipment as shown in Figure 3. Obtaining a Mass - Repeat for Each Sample 1. Crease a piece of weigh paper and place it on the silver scale of the mass balance as in Figure 4. 2. Close the doors on the mass balance to eliminate room convection currents, and press the button reading Tare or Zero in order t An excavator is a power-driven machine mostly used in earthmoving operations. Heavy equipment typically used for excavating include the following: Backhoes: Backhoes are used for surface or subsurface excavation of solids and sludge. Backhoes are used to dig below the surface, such as trenches, building footings and foundations

A List of Chemistry Laboratory Apparatus and Their Uses

  1. In Part A of this lab, a metric ruler will be used to measure length in centimeters (cm). In Part B, a beaker and a graduated cylinder will be used to measure liquid volume in milliliters (mL). In Part C, an electronic balance and a triple-beam balance will be to measure mass in grams (g)
  2. This is a digital balance used for measuring mass with 0.1 mg precision. 04. of 40. Beakers in the Chemistry Lab Westend61/Getty Images. 05. of 40. Centrifuge Fuse/Getty Images. A centrifuge is a motorized piece of laboratory equipment which spins liquid samples to separate their components. Pipets (pipettes) are used to measure and.
  3. 2. Beaker • Beakers hold solids or liquids. • Very poor accuracy - should only be used to estimate volume • Note the size capacity (250 mL in this case) There are four sizes of beakers for you to use in your lab desk. 3. Beaker Tongs Beaker tongs are used to move beakers containing hot liquids
  4. 3. Measuring Spoons. Measuring spoons are specially used to measure cooking ingredients. It's essential equipment in the kitchen. We can't measure the right amounts of liquid or solid cooking ingredients without measuring spoons. It plays an important role in measuring cooking ingredients. 4. Mixing Bowl
  5. Food processing equipment is an umbrella term referring to the components, processing machines, and systems used to handle, prepare, cook, store, and package food and food products.Although this equipment is primarily aimed toward the transformation—i.e., increasing the palatability, consumability, and digestibility—or preservation—i.e., extending the shelf life—of food, some pieces of.
  6. a procedure for obtaining the mass of a sample by first weighing a container and then weighing the container with the sample. An unknown rectangular solid has a mass of 140.417g and measures 5.05cm by 2.50cm by 1.25cm. Calculate the density of the unknown solid A piece of green jade has a mass of 26.123g. If the sample of jade displaces.

A number of pieces of chemistry glassware are used to accurately measure volumes; the most obvious being the graduated cylinder, or measuring cylinder, which can come in a variety of sizes.. For measuring volumes of solutions more precisely, a volumetric pipette can be used.These come in a variety of sizes, each measuring a fixed volume of solution The devise that is used for measurement of certain physical quantity is called as measuring instrument. There are two main types of the measuring instruments: analogue and digital. The analogue instruments indicate the magnitude of the quantity in the form of the pointer movement. The digital measuring instruments indicate the values of the quantity in digital format that is in numbers, which. For both solids and liquids, a balance can be used to measure mass; however, methods for determining volume are different for solids and liquids. As liquids can flow and take the shapes of their containers, glassware such as a graduated cylinder or volumetric flask can be used to measure the volume of a liquid Equipment used for field measurements will be handled, transported, shipped, stored and operated The equipment inventory list for each instrument or piece of equipment will include: 1.2.1.1. A description of the property and software, if applicable . 1.2.1.2. Manufacturer or vendor name . 1.2.1.3. Model number most widely used method for obtaining data on soil moisture. Because it is the only direct way of measuring soil moisture, it is required for calibrating the equipment used in the oth°sr methods. Russell (II, 1950) 1 reporting on work completed in 1843 an

Most commonly used is the Erlenmeyer flask, which looks like an upside-down funnel. This piece of equipment is used to hold liquids, but because of its narrow neck is not generally used to mix. A watch glass is a popular type of chemistry lab instrument. It's a concave piece of glass customarily used to hold solids, evaporate liquids and heat small quantities of a substance. 4. Crucible Crucible with lid. Photo: @safestallbd Source: Facebook. This apparatus is a small receptacle usually made using porcelain Density of Solids and Liquids by Peter Hidnert and Elmer L. Peffer* Density data may be used for obtaining relationships between density, chemical com-position, thermal and mechanical treatments of materials, etc. This circular defines density and specific gravity, describes 11 methods (hydrostatic weighing, picnometer, flotation Sewing Tools and Equipment Sewing equipment different tools are used in garment construction. The skillful use of the different sewing equipment will help take body measurement and drafting pattern with accuracy and speed. Success in sewing calls for the right tools at the right time. All tools must be appropriate in a proper order and one must know how to use them to save time and produce the.

Micro pipettes are the standard laboratory equipment used to measure and transfer small volumes of liquids. Mohr Pipet. A Mohr Pipet is a graduated pipet that is designd to deliver small portions of a liquid or solution. These portions are determined by recording the difference between the initial and final volume readings Weather instruments are devices used by atmospheric scientists to sample the state of the atmosphere, or what it's doing, at a given time. Unlike chemists, biologists, and physicists, meteorologists don't use these instruments in a lab. They're used in the field, placed outdoors as a suite of sensors which, together, provide a complete picture of weather conditions

lab equipment

Video: 20 Different Types of Measuring Tools - Home Stratospher

Laboratory glassware refers to a variety of equipment used in scientific work, and traditionally made of glass.Glass can be blown, bent, cut, molded, and formed into many sizes and shapes, and is therefore common in chemistry, biology, and analytical laboratories.Many laboratories have training programs to demonstrate how glassware is used and to alert first-time users to the safety hazards. Used to obtain pure crystalline solid Use the proper solvent or solvents--test if necessary; a proper solvent will exhibit a big solubility difference over a small temperature range. Recrystallization or crystallization a. use an Erlenmeyer flask, it is specificially designed for this purpos The subsoiler is a primary tillage tool, used in the fall, that is similar to a chisel plow. It is typically designed to pene-trate 12 to 22 inches deep to alleviate soil compaction. Subsoiling is often used to loosen compacted areas of fields where heavy loads have passed. The amount of distur-bance will depend upon the shape of the shank and. 4.5 These test methods provide a means for determining hydraulic conductivity at a controlled level of effective stress. Hydraulic conductivity varies with varying void ratio, which changes when the effective stress changes. If the void ratio is changed, the hydraulic conductivity of the test specimen will likely change, see Appendix X2.To determine the relationship between hydraulic. 1.1 Gravimetric analysis is used to determine total suspended solids (TSS) and total volatile solids (TVS), also known as volatile suspended solids The results from duplicate analyses are used to evaluate analytical or measurement precision but not the precision of sampling, equipment in the laboratory

Basic Equipment Used in Volleyball. More than 24 million Americans and 800 million people worldwide have discovered their passion for volleyball, a sport that originated in America and is now over 117 years old and a popular Olympic event. Volleyball provides a great workout, as well as a chance to participate in a. Percent Solids to Specific Gravity Conversion of Slurry. Here is the formula for specific gravity of a slurry, S is: S = specific gravity of slurry. Si= specific gravity of liquid phase. Ss= specific gravity of solids phase. Cw = concentration of solids by weight. Cv= concentration of solids by volume

Pasteur pipets may be calibrated for use in operations where the volume does not need to be known precisely, such as for measurement of solvents need for extraction and for washing a solid obtained following crystallization. To calibrate a Pasteur pipet, weigh 0.5 g (0.5 mL) of water into a small test tube on a balance The commercial measurement system in the United States continues to use non-SI units for practical applications and manufacturers in this industry continue to use U.S. Customary dimensions. Since commercial applications in the United States use units other than SI or other accepted metric units, this document references common units in current use Carry out checks to ensure that transfer lines, hoses and other pieces of equipment used to transfer products from one area to another are correctly connected and do not pose a contamination risk. Ensure all materials, bulk containers, major items of equipment and rooms used are labelled (or otherwise identified) Yield monitors have variances between each model, although there are some defining pieces of equipment that are used in the yield monitoring process. These sensors are key components of the yield monitoring process and help to provide further knowledge for the farmer, as well as more accurate results when collecting data. Mass Flow Senso

Di et al. 13 used a gradient boosting machine to predict the susceptibility of debris flow in a watershed, and the results were compared with the outputs deduced by logistic regression, k-nearest. Water exists as a solid, liquid and as a gas. What name is used for solid water and gaseous water? In a solid, the particles pack together tightly in a neat and ordered arrangement. The particles. require the use of personal protective equipment. If PPE has to be used, the supervisor must select the proper equipment and require its use. HAZARD CONTROL Eliminating hazards through engineering or administrative control measures is the best way to protect people For measuring moisture content in grain, wood, food, textiles, pulp, paper, chemicals, mortar, soil, coffee, jute, tobacco, rice and concrete, electrical-resistance-type meters are used. This type of instrument operates on the principle of electrical resistance, which varies minutely in accordance with the moisture content of the item measured

15 Different Types of Kitchen Measuring Tools and Gadgets

  1. The main pieces of surveying equipment in use around the world are the following: theodolite, measuring tape, total station, 3D scanners, GPS/GNSS, level and rod. Most survey instruments screw onto a tripod when in use. Analog or digital tape measures are often used for measurement of smaller distances
  2. Graduated and adjustable measuring cups are used to measure dry ingredients, such as flour, sugar, oats, rice and solid ingredients, such as shortening and peanut butter. The single measure cups are generally found nested in a graduated set of ¼ cup, 1/3 cup, ½ cup, and 1 cup measures
  3. Laboratory Apparatus<br />12.)Iron clamp-An iron clamp is a piece of laboratory equipment used to hold things and is placed in an iron stand to elevate other equipment.<br /> 14. Laboratory Apparatus<br />13.)Iron stand-A metal rod attached to a heavy metal base
  4. Home: Help Center: Answers What units of measurement are used for data storage? A: The smallest unit of measurement used for measuring data is a bit.A single bit can have a value of either 0 or 1. It may contain a binary value (such as On/Off or True/False), but nothing more. Therefore, a byte, or eight bits, is used as the fundamental unit of measurement for data
  5. A tub grinder is a very useful piece of equipment because it can be used on a range of debris matter (Fig. 29.6). Chipped vegetative material can be reused in several valuable ways, such as a soil amendment to control erosion, stock for paper factories, and as a landfill cover material

The seven basic types of temperature measurement sensors discussed here are thermocouples, resistive temperature devices (RTDs, thermistors), infrared radiators, bimetallic devices, liquid expansion devices, molecular change-of-state and silicon diodes. 1. Thermocouples. Thermocouples are voltage devices that indicate temperature measurement. 1. Scope. 1.1 These test methods cover the determination of the specific gravity of soil solids that pass the 4.75-mm (No. 4) sieve, by means of a water pycnometer. When the soil contains particles larger than the 4.75-mm sieve, Test Method C127 shall be used for the soil solids retained on the 4.75-mm sieve and these test methods shall be used. 2. Get a piece of wood which is straight and flat. It should be about 5 cm wide, and a little more than 4 m long. You can also use a shorter length, if the distance you are going to measure is shorter. 3. It is best to use a planed piece of wood, but if you cannot get one you may use a straight wooden pole specific characteristics. The equipment used for reclamation projects is adapted primarily from technologies already in use in the min-ing industry, as well as in construction and other solid waste management operations. In general, landfill reclamation follows these steps: Excavation An excavator removes the contents of the landfill cell

Used as a method for recovering valuable metals, such as uranium, from solution. J. Jaw crusher - A machine in which rock is broken by the action of steel plates. Jig - A piece of milling equipment used to concentrate ore on a screen submerged in water, either by the reciprocating motion of the screen or by the pulsation of water through it. This means that TSS is a specific measurement of all suspended solids, organic and inorganic, by mass. TSS includes settleable solids, and is the direct measurement of the total solids present in a water body. As such, TSS can be used to calculate sedimentation rates, while turbidity cannot 1,6 Motor Graders. Built with decades of design experience, you'll find the perfect Cat® motor grader for your grading application. With world-class cabs, advanced hydraulics, control-type options and technology options, you'll complete your grading projects on time and at a lower cost. Filter By Field measurements used to verify instrument output may dictate the frequency of visits, as well as the method and frequency of data retrieval. Appropriate field documentation is important for transducer calibration and calibration checks, for recording equipment malfunctions, for recording changing site conditions, and for data computation

Chemistry for Kids: Chemistry Lab Equipmen

Beginner's Glossary BEGINNER'S PROJECT GLOSSARY Note: Almost all of the words in this list are taken directly from the Beginners pages (yes, I actually read through the entire thing!). I have also thrown in a few words that I think you will need to know (or be able to find a definition for). I have assumed that nothing RR related is too obvious to be defined 7. Design Rules. 8. Cost Drivers. Turning is a form of machining, a material removal process, which is used to create rotational parts by cutting away unwanted material. The turning process requires a turning machine or lathe, workpiece, fixture, and cutting tool. The workpiece is a piece of pre-shaped material that is secured to the fixture. INTRODUCTION. This is a guide to Connecticut sales and use taxes for manufacturers, fabricators and processors doing business in the State of Connecticut. The main focus of the guide is on the sales and use taxes as they apply to the manufacturing industry. Manufacturers, fabricators and processors are defined in Section I of this guide

Measuring mass does not necessarily measure weight, as weight changes depending on the effect of gravity. Mass, however, does not change regardless of where an object is located. The amount of matter remains the same. To measure mass, scientists use various tools depending on the size and location of the object Measurement of length, Mass, Volume and Density Readings Before you begin this laboratory read chapter 1 of the textbook. Objectives After completing this lab, you will be able to: 1. Make measurements to the nearest 1/10 of a millimeter using a meter stick. 2. Use a vernier caliper to make measurements to the nearest 1/10 of a millimeter. 3 Total solids are dissolved solids plus suspended and settleable solids in water. In stream water, dissolved solids consist of calcium, chlorides, nitrate, phosphorus, iron, sulfur, and other ions particles that will pass through a filter with pores of around 2 microns (0.002 cm) in size. Suspended solids include silt and clay particles. To measure the specific heat capacity of a metal (solid block method) This method is suitable for a metal which is a good thermal conductor, e.g., copper or aluminium. A cylindrical block of the metal is drilled with two holes, one to receive an electric immersion heater and the other a thermometer. A little oil may be used in the holes to. 2.4.2. Measure of Spread of Data. The spread of the data is a measurement of how closely together repeated measurements are to each other. The standard deviation is the most commonly used measure of the spread of experimental measurements. This is determined by assuming that the experimental measurements vary randomly about the mean, so that.

Commonly Used Lab Equipment - Rice Universit

One major measurement result can be composed of many preliminary measurements. For example, say you need to determine the mass of something using a precision electronic balance. Being conscientious, you verify the operation of the balance before use, using a certified mass standard at or near the range you plan to measure When a piece of equipment wears out and is replaced by a new unit that provides essentially the same process function as the old unit, then it is not uncommon for the new piece of equipment to inherit the old equipment's name and number (often an additional letter suffix will be used, e.g., H-101 might become H-101A) The two most common methods used to determine the chemical composition of an alloy (or any metal) are X-ray fluorescence spectroscopy (XRF) and optical emission spectroscopy (OES). XRF is non-destructive, however, OES is more sensitive than XRF to lighter elements

Graduated cylinders are used for precise and accurate measurement. Smaller sizes can be more accurate, but hold less volume, while larger sizes sacrifice accuracy for volume. View more graduated cylinders. A mortar and pestle is used to crush up solid chemicals into smaller pieces, or to grind solids into fine powder. This makes dissolving. It is commonly used to produce a wide variety of products, including electrical wire, cooking pots and pans, pipes and tubes, automobile radiators, and many others. Copper is also used as a pigment and preservative for paper, paint, textiles, and wood. It is combined with zinc to produce brass and with tin to produce bronze When a machine is used to remove portions from a piece of metal, the process is known as machining. Typically, the process is performed on a lathe, which will rotate the metal against tools that trim corners and edges to cut the piece down to a desired shape or measurement Biotech/Pharmaceutical Facility Closure: Massachusetts. One of our previous project clients recommended our services to Synta Pharmaceuticals to help with closing a facility consisting of three different buildings. The entire facility needed full clearance and contained an array of over 400 pieces of R&D equipment. Read More

Measuring density of solid, liquid and viscous samples on an analytical or precision balance - fast and easy process with Density Kit and balance application. We explain best procedures for density determination: buoyancy and displacement methods, both based on Archimedes' Principle. More Plastic limit test is one of the laboratory tests used internationally to differentiate or classify soils into groups. As the starting procedures of liquid limit test and plastic limit test are common, the both tests are executed at the same time in most of the purposes. The Swedish Scientist, A. Atterberg defined the plastic limit as, boundary of soil between the plastic and solid state. The. For training about proper handling and restraint techniques with animals, contact the ULAM animal staff at (734) 764-0277. The ventilation system is certified for a specific purpose - use of hazardous materials or biological substances - or for general non-hazardous conditions such as general exhaust of heat or steam

Measuring instrument - Wikipedi

It is preferable that a second piece of equipment be used for replacement during breakdown and routine maintenance periods of the regular equipment. At large sanitary landfills serving more than 100,000 persons, or handling more than 310 tons of solid wastes per day, more than one piece of equipment will be required. At these sites, specialized. Abstract. These test methods cover the determination of the specific gravity of soil solids passing a sieve by means of a water pycnometer. Soil solids for these test methods do not include solids which can be altered by these methods, contaminated with a substance that prohibits the use of these methods, or are highly organic soil solids, such as fibrous matter which floats in water Equipment Guide for processing and measuring dry materials / solids. Global market leader in Screw Conveyors and amongst the most prominent players in the field of Bulk Solids Handling & Processing Equipment. More info > Thayer Scale is a leading global manufacturer of equipment used for continuous weighing and feeding of bulk materials.

Measurements of a variety of properties (e.g., hardness, reflectivity) can be used to identify particular materials. (Boundary: At this grade level, mass and weight are not distinguished, and no attempt is made to define the unseen particles or explain the atomic-scale mechanism of evaporation and condensation.) By the end of grade 8 When the machine using a gear is mass produced, then so is the gear which is made to a certain production lot size, spreading the unit cost of the gear by taking advantage of the economy of scale. On the other hand, users utilizing the machine after it has been manufactured and when one or two gears need replacement, they often face a high. Machine & Equipment Hazardss. Electrical Hazards - equipment that uses electricity as a power source is a potential electrocution hazard. Check power cords, switches and connections for exposed wires or broken parts. Amputation & Caught-in Hazards - machine guards on equipment are installed to protect our employees from moving parts A close-up view of a section of a water-to-air heat exchanger. Image Credit: Alaettin YILDIRIM/Shutterstock.com. Heat exchangers are devices designed to transfer heat between two or more fluids—i.e., liquids, vapors, or gases—of different temperatures. Depending on the type of heat exchanger employed, the heat transferring process can be gas-to-gas, liquid-to-gas, or liquid-to-liquid and. The lathe is a machine tool used principally for shaping pieces of metal (and sometimes wood or other materials) by causing the workpiece to be held and rotated by the lathe while a tool bit is advanced into the work causing the cutting action. A solid machine mandrel is generally made from hardened steel and ground to a slight taper of.

difficult and slow to measure the volume and mass of individual particles. Helium pycnometry [9,10] can be used to measure the true density of the solid backbone of a porous material, as long as all the pores are accessible by helium gas flowing through the sample. A loose powder compact, like that measured here A few things to remember: When calibrating the resistance of an RTD, use a 4-wire connection, if possible. Of course, when you calibrate an RTD temperature transmitter that is configured for 3-wire measurement, you need to use 3 wires. Make sure you use 3 similar wires and that you make good contacts An ophthalmoscope is an instrument used for examining the interior structures of the eye, especially the retina, consisting of a mirror that reflects light into the eye and a central hole through which the eye is examined. A binocular indirect ophthalmoscope (BIO) is worn on an eye doctor's head in order to have the use of both hands to examine.