Linear Measurements MCQ Quiz in मराठी - Objective Question with Answer for Linear Measurements - मोफत PDF डाउनलोड करा

Explanation:

Universal Bevel Protractor Vernier Scale

Definition: A Universal Bevel Protractor is a precision instrument used for measuring angles with high accuracy. It consists of a base, a graduated circular scale, and a vernier scale that allows for fine measurements. The vernier scale is an essential part of the protractor, enabling users to measure angles to a finer degree than the main scale alone.

Understanding Vernier Scale: The vernier scale on a Universal Bevel Protractor is designed to provide precise readings of angles. This scale typically consists of a number of divisions that correspond to fractional parts of the main scale divisions. By carefully aligning the marks on the main scale and the vernier scale, users can read angles to a finer resolution.

Number of Divisions: The number of divisions on the vernier scale of a Universal Bevel Protractor is 24. This means that the vernier scale is divided into 24 equal parts. Each division on the vernier scale represents a fraction of the smallest division on the main scale, allowing for precise measurement of angles.

Working Principle: When measuring an angle using the Universal Bevel Protractor, the main scale provides a coarse measurement, while the vernier scale provides a fine measurement. To read the angle, users first note the main scale reading where the zero mark of the vernier scale aligns. Then, they find the vernier scale division that aligns most closely with any division on the main scale. The combination of these readings gives the precise angle.

Advantages:

• High precision: The vernier scale allows for measurements with high accuracy.
• Ease of use: The design of the Universal Bevel Protractor makes it straightforward to measure angles accurately.
• Versatility: It can measure a wide range of angles, making it useful in various applications.

Disadvantages:

• Delicate: The precision nature of the instrument means it can be sensitive and prone to damage if not handled carefully.
• Learning curve: Users may need practice to become proficient in reading the vernier scale accurately.

Applications: Universal Bevel Protractors are commonly used in fields requiring precise angle measurements, such as machining, metalworking, and carpentry. They are essential tools in quality control processes and are used by professionals to ensure the accuracy of manufactured parts and assemblies.

Explanation:

Shrink rule:

• The shrink rule is a special type of rule which is used to ease pattern-making.
• Shrink rule is used for laying out casting patterns and core boxes by pattern makers.
• The shrink rule looks like a simple rule, just the graduation on it is bigger than a simple rule because shrinkage allowance is added to each division of the shrink rule.
• It is used while making a pattern or core box.
• This type of steel rule is like a standard rule.
• The only difference is that its inch or mm markings are slightly larger than the standard rule.
• If the shrinkage allowance is 10 mm per meter of length, the 30 cm shrinkage scale will be 3 mm longer than the normal measuring scale.
• Different shrink rules are used for different pattern materials.
• It is also known as the contraction scale or shrinkage scale or pattern makers scale.
• This scale provides a ready-made method of assigning shrinkage allowances to a pattern.
• This type of rule is mostly used by pattern makers.
• Shrink rule is mostly made of steel or wood.

Hook rule:

• A reversible, removable hook grabs the edge of an object for easy alignment.
• Also known as machinists' rules, these rulers ensure reliable, repeatable measurements.
• A hook grabs the edge of an object for easy alignment.
• These rulers are corrosion-resistant stainless steel and have wear-resistant etched markings.
• All are flexible for measuring slightly curved surfaces.

Short steel rule:

• This set of five small rules together with a holder is extremely useful for measurements in confined or hard-to-reach locations which prevents the use of ordinary steel rules.
• It is used suitably for measuring grooves, short shoulders, recesses, keyways, etc. in machining operations on shapers, millers, and tool and die work.

Flexible rules:

•  Flexible rules are usually half an inch wide and 1/64 inch thick.
• While most steel rules are 12 inches long, they are available up to 144 inches (12 feet) long.
• It is capable of being bent, usually without breaking.
• A tape measure or measuring tape is a flexible ruler used to measure length or distance.